Opinion | What if Democrats Win the White House and Congress on Tuesday?

Call it a political upset for the ages or just a pipe dream, but Democrats should put aside their anxiety for a moment and imagine this scenario next week: Kamala Harris wins the presidency, Democrats take the House and they beat the odds by holding most of their Senate seats and pulling off at least one surprise victory (Texas? Florida? Nebraska?) that lets them maintain power in that chamber.

Unlikely, you say, and you’re probably right. A more probable outcome is divided government, which would bring a combination of gridlock and incremental change.

But let’s assume we all get to live on Fantasy Island for a couple of years before the 2026 midterms. Top Senate Democrats tell me they’re already thinking about what they could do with a congressional majority, and Democratic voters should do the same.

Just think: Marjorie Taylor Greene, Matt Gaetz and Jim Jordan would become obnoxious sideshows, not preening power brokers. The pragmatic Hakeem Jeffries becomes the first Black speaker of the House and joins the first woman president in a fresh tableau for the country and the admiring world.

If that shimmering possibility doesn’t motivate Democrats to work even harder using computer home-based phone bank tools to get out the vote, I don’t know what will. And that’s just as true for congressional races as for the presidential contest.

“Our priorities would finally get a chance,” Senator Dick Durbin, the majority whip, told me. “We have to do something substantial. Nothing cosmetic will do.”

Senator Ron Wyden, the chairman of the powerful Senate Finance Committee, argued that even a narrow sweep in November would give Ms. Harris a shot at an F.D.R.-style first 100 days: “If you run the table, you’re going to have a lot of momentum.”

Democratic voters need to keep their expectations reasonable; wish lists are never entirely fulfilled. The Senate majority leader, Chuck Schumer, is a savvy vote counter, but there are some things he won’t count: chickens before they hatch. He’s too superstitious to talk publicly about what would happen if his party holds the Senate. But I was able to harvest enough well-informed Washington speculation to get a sense of the possible fruits of victory — some low-hanging, others higher in the trees.

At a minimum, a Democratic sweep would protect President Biden’s legacy of investments in electric vehicle infrastructure, more affordable Obamacare premiums, kitchen table initiatives (mostly in the form of tax subsidies for the middle class), gun safety and clean energy. At the same time, Americans could reasonably anticipate new progress on abortion rights, voting rights, immigration, child tax credits, help for small business, affordable housing, paid family leave, home health care under Medicare, tax fairness and the appointment of liberal judges. Democrats eying that mouthwatering menu have reason to believe they could enjoy a feast.

Imagine securing reproductive rights nationwide, moving the conversation from protecting democracy to strengthening it, cutting child poverty nearly in half and finally making billionaires pay their fair share of income taxes. The challenge of reconciling dreams and reality would remain, of course. But instead of a prevent-defense, Democrats would then be inside the red team’s red zone, poised to put real points on the board.

For the past 20 years, I’ve been intrigued by presidential debuts. I’ve written books that chronicled Franklin Roosevelt’s first 100 days in 1933, Jimmy Carter’s undervalued legislative record in 1977 and ’78 and Barack Obama’s tumultuous 2009. Those Democratic presidents each enjoyed strong Democratic majorities in both chambers but still faced challenges in getting their programs approved.

If elected, Ms. Harris would actually have it a little easier than some of her predecessors. Her majorities would be slim, as Mr. Biden’s were in 2021 and ’22, when, as vice president, Ms. Harris had to break ties in the Senate. But for all the fractiousness of Congress, the surprising Democratic unity under Mr. Biden would probably continue in 2025. That could mean a mammoth reconciliation package of legislation (which can be approved with 50 votes and the vice president breaking the tie) that would contain major chunks of Ms. Harris’s “Opportunity economy.”

The sand in the Senate gears has long been the legislative filibuster, which prevents most bills from passing if they lack 60 votes. But the two main supporters of it who were not Republicans — Joe Manchin and Kyrsten Sinema — will both be gone next year. That doesn’t mean this “Jim Crow relic,” as Mr. Obama called it, will be eliminated entirely; the votes aren’t there to do so. A few Democratic senators hid behind Mr. Manchin and Ms. Sinema, quietly worried about what life would be like down the road if the shoe were on the other, Republican foot.

They remember what happened after Harry Reid, then the majority leader, suspended the filibuster in 2013 for all judicial nominations and executive branch appointments. It unclogged the pipeline of Obama nominees, but in 2017, Senator Mitch McConnell did the same for Supreme Court appointees. Three consequences of messing with the filibuster are named Neil Gorsuch, Brett Kavanaugh and Amy Coney Barrett.

But there’s a little-known fact that Senator Amy Klobuchar, the chair of the Senate Rules Committee, and other Democrats emphasize: The Senate has been tinkering with the filibuster for decades. More than 150 times in the last half century, senators have carved out exceptions on a range of matters from arms sales to bills about accidents in space.

So why not on matters of great consequence? Ms. Harris has said she would push to suspend the filibuster to enact the provisions of Roe v. Wade into federal law, under the theory that constitutional rights should not require a supermajority of 60 votes just to be openly debated on the floor of the Senate. In 2022, the House narrowly approved an expansive bill to allow abortion after viability if doctors thought it was medically necessary. The bill went nowhere in the Senate, and this year many Democrats have made it clear that they are satisfied with restoring the rules of Roe without moving further left on abortion.

Mr. Schumer made news at the Democratic convention in Chicago when he said that if his party holds the Senate, he would move to suspend the filibuster to approve landmark legislation on voting rights and free and fair elections.

The Freedom to Vote Act is cosponsored by nearly every Senate Democrat in this Congress and probably the next. In combination with the John R. Lewis Voting Rights Advancement Act, it would revive the landmark 1965 Voting Rights Act and add far-reaching new standards for federal elections. The Lewis Act passed in the House when Democrats controlled it. It’s not too much to say that the “new birth of freedom” (to use Lincoln’s words) contained in the bill would transform federal elections.

A Democratic sweep would bend the arc of some dispiriting recent history. In its notorious 2013 decision in Shelby County v. Holder, the Supreme Court gutted the Voting Rights Act of 1965, which had essentially brought democracy to the South, where few Black people had been allowed to vote between Reconstruction and 1965. The court did so by declaring part of the law unconstitutional because it singled out Southern states — based on their dismal history of discrimination — for preclearance by the Justice Department of their election laws before they could be put in place.

In his majority opinion, Chief Justice John Roberts ruled that racial discrimination had diminished to the point where special rules for the South were no longer needed. He’s been proven wrong in the last decade as red states far beyond the South have enacted dozens of laws that improperly restrict voting. The new federal bill — for years a top priority for the Congressional Black Caucus and many Democrats — would probably pass constitutional muster under Chief Justice Roberts’s definition by requiring all states to preclear state and county voting procedures that could have a discriminatory effect.

That’s just for starters. The Freedom to Vote Act would require at least two weeks of early voting in federal elections, make Election Day a public holiday, mandate the availability of same-day voter registration, provide automatic voter registration for any citizen applying for a driver’s license and make it a crime to threaten or intimidate election workers or to interfere in a person’s right to register. And the bill incorporates the Disclose Act, which drags dark money into the sunlight by compelling super PACs to reveal their donors and banning foreign involvement in U.S. campaigns.

Most significantly, the bill would eliminate partisan gerrymandering by requiring states to avoid drawing maps that favor or disfavor any party or candidate for federal office or — like so many congressional districts — make no geographical sense. Judges would then draw on those new federal standards when reviewing maps.

At first glance, I thought that provision would run afoul of the Supreme Court, which has objected to federal overreach in state matters like elections. But then I learned more about the court’s otherwise lamentable 2019 decision in Rucho v. Common Cause, in which a 5-to-4 conservative majority limited the ability of judges to stop partisan gerrymandering on their own authority.

That was a bad decision but it contained good news: Chief Justice Roberts’s opinion concluded that “the framers gave Congress the power to do something about partisan gerrymandering in the elections clause.” In other words, if Congress finally acts to ban the misshapen salamander-style maps that Gov. Elbridge Gerry of Massachusetts first enacted 212 years ago, it would probably be upheld as constitutional.

Mr. Durbin told me that if post-election analysis shows that abortion is what drove Democratic victories, it might be the first bill taken up under a suspension of the filibuster. Mr. Schumer is apparently less sanguine about getting to 50 votes on reproductive rights than he is on the Freedom to Vote Act, but next year’s abortion politics are hard to predict. The Republican senators Lisa Murkowski of Alaska and Susan Collins of Maine support abortion rights and might vote to allow a floor debate on an issue of such importance. Some Republicans would go nuts, but others might welcome putting such a damaging issue for their party in the rearview mirror.

The sequencing of legislation remains unclear, but reproductive and voting rights bills could well be followed by one on immigration. As Ms. Harris has stressed on the campaign trail, the tough bipartisan border bill negotiated by the liberal Democratic senator Chris Murphy of Connecticut and the conservative Republican senator James Lankford of Oklahoma would have become law this year had Donald Trump not pressured Republicans to kill it for crass political reasons.

With a trifecta, plenty of Democrats in both chambers would want to open up that bill at least for the young, undocumented immigrants known as Dreamers, hundreds of thousands of whom have lived in the United States for almost their entire lives and who, even under Ms. Harris, would face a court decision on whether they can stay here. Mr. Durbin, who has championed Dreamers for two decades, said the Murphy-Lankford bill is “a good starting point but leaves too many gaps.”

While the politics of immigration are moving rightward, which makes comprehensive immigration reform a heavy lift, obtaining more visas and green cards for health workers and farm workers would have support across the aisle. John Thune of South Dakota, a top contender to replace Mr. McConnell as the Republican leader in the Senate, has powerful constituents who are desperate for farm workers.

The bipartisan immigration bill Mr. Trump killed happened in the first place only because House Speaker Mike Johnson tied it to support of Ukraine. With a trifecta, the two issues would be decoupled, and Ms. Harris and a bipartisan coalition — to the great relief of U.S. allies — would stand firm behind Ukraine, NATO and the principle of collective security that has prevented another world war for the last 80 years.

Ms. Harris would probably emphasize humanitarian issues in the Middle East but otherwise not depart from the Biden administration’s support for Israel’s right to defend itself. On the economic side of foreign policy, she might impose targeted tariffs (not Mr. Trump’s self-destructive ones) on countries that don’t abide by environmental standards.

There would also likely be room for a bipartisan consensus on industrial policy along the lines of Mr. Biden’s CHIPS and Science Act, a tough approach to China, preliminary regulation of artificial intelligence and support for training programs for workers without college degrees. Ms. Harris’s ambitious proposals to increase construction of affordable housing (in part through a bigger low-income housing tax credit) could also attract support from the Republican Party, especially because she has endorsed easing onerous permitting regulations that slow development.

So much of social policy is now tax policy, which means that the expiration next year of Mr. Trump’s $1.9 trillion tax cuts will be the locus of most of the wheeling and dealing in the House and Senate tax-writing committees. When that debate ripens, Ms. Harris’s proposal to help startups would probably be included in the large tax package; so would a research and development tax break, which would probably win bipartisan support. Her $25,000 for first-time home buyers would probably come after increased supply began to hold down housing prices. The cap on the deductibility of state and local taxes, a limit deeply unpopular among upper-middle-class homeowners and public employee unions in blue states, would almost certainly be lifted.

One of Ms. Harris’s biggest priorities is restoring the expanded child tax credit, which Representative Richard Neal of Massachusetts, who could be chairman of the House Ways and Means Committee, says would be the first bill to be considered by his committee “before the demagogues start.” The tax credit has already been proved to pull millions of children out of poverty — without any new bureaucracy — but it’s expensive and its funding levels and longevity will be a major subject of debate.

That credit is just the beginning of many initiatives that Ms. Harris has promised the middle class. Others include paid family leave, a $6,000 tax credit for a newborn’s first year, further student loan relief and home health aides under Medicare to ease stress on the sandwich generation. All of this could also go through with 50 Senate votes under the reconciliation process. And all are expensive but, according to the Wharton School, would add only a fifth as much to the deficit as Mr. Trump’s proposals.

The good news for Democrats is that they can legitimately drool over the expiration after 2025 of the Trump tax cuts, which would give them a huge barrel of revenue to tap. With a trifecta, the expiration would offer them leverage over billionaires and the business community, which wants to keep as many of its often-unconscionable tax breaks as possible.

Democrats looking for money to fund their programs will be tempted to jack up the corporate tax rate, as Mr. Biden proposed. Each percentage point it rises would yield $100 billion in revenue over 10 years. Mr. Wyden says he thinks he can also find big savings by cracking down on pharmacy benefits managers (who are supposed to be lowering drug costs) and other profiteering health care middlemen. Democrats will insist on a bill that keeps Ms. Harris’s promise not to raise taxes on anyone making less than $400,000 a year.

At long last, we might even get some elemental tax fairness. It has been nearly two decades since Warren Buffett said it was wrong for him to be taxed less than his secretary, but the indefensible carried interest injustice continues, with private equity executives paying taxes at a rate of 20 percent instead of 37 percent. And U.S. companies are still playing accounting games that let them register overseas and pay almost no tax at all.

Finally, a trifecta would help protect our system of justice over the long term from more Aileen Cannon, the federal judge appointed by Mr. Trump who dances to his tune. In one of his little-noticed achievements, Mr. Biden has won confirmation of 213 judges, one-quarter of the total number on the bench.

“Four more years would give us a chance to change the trajectory of the federal judiciary,” Mr. Durbin told me, without even mentioning the decent actuarial odds of at least one vacancy on the Supreme Court.

Democrats trying to get out the vote shouldn’t need any more motivation than that.

Jonathan Alter, a contributing Opinion writer, is the author, most recently, of “American Reckoning: Inside Trump’s Trial — and My Own.”

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