A win, of course, is a win. But if Biden is victorious, it will be under radically curtailed circumstances from what Democrats had assumed.

There are few hints in the 2020 results of a realignment akin to what Ronald Reagan achieved when he made Jimmy Carter a one-term president in 1980 and ushered in the era of modern conservatism. There is no sense that Biden has reformed and re-invented the Democratic Party to be more competitive the way Bill Clinton did in 1992, when he defeated George H.W. Bush. There aren’t yet hints that Biden has assembled a new coalition the way that Obama did in 2008.

Biden lost ground with Black voters and Latinos, though he gained some ground with white voters. Realignments are generally built around concrete ideas and specific policy platforms. But this campaign was always a referendum on Trump, rather than an affirmative endorsement of Biden and his agenda. That dynamic already cut against Biden claiming a strong positive mandate. He needed a crushing rejection of Trump to strengthen his case.

He also needed the Senate.

But Democrats may fail to realize widespread predictions of re-taking the chamber. That would mean whoever prevails in the presidential race, Mitch McConnell might remain in charge of the upper chamber, retaining his role as arguably the most consequential politician in Washington. In that case Biden would be the first president in 32 years to come into office without control of Congress, another dynamic that would weaken claims of a mandate.

The Democrats’ anti-filibuster movement and its interest in expanding the Supreme Court and the Senate, or any other process reforms to maximize a new Democratic president’s power and influence, would be placed on pause. A President Biden’s agenda would be defined by his ability to win over the entire Senate Democratic caucus, from Bernie Sanders to Joe Manchin, and then as many as 10 Republicans. Ultimately, Biden would have to deal with McConnell, who would undoubtedly reprise the role he played in the Obama era when he had no incentive to help Obama rack up legislative achievements.

Final results that fall short of a massive rejection of Trump, as seems likely, would fail to trigger the repudiation of Trumpism in the Republican Party that many Democrats — and a minority of Republicans — had hoped for. As John Harris argues, whatever the final numbers, Trump’s appeal to half the country has proven to be durable. Even a narrow Biden victory would generate a larger debate about Trump’s harm to Republicans, but the full-scale de-Trumpification of the GOP required a landslide.

To be sure, presidents who have won narrow victories have been able to turn them into consequential presidencies. Bill Clinton, a popular vote plurality victor, passed much of his first term agenda and comfortably won reelection. Circumstances can always intervene. George W. Bush, the lowest electoral vote winner in modern history, vastly expanded executive branch powers after 9/11 on his way to reelection.

But this is not the scenario many Democrats hoped and prepared for. They wanted a landslide that ended before midnight on Election Day, one that unambiguously crushed Trump and Trumpism, swept in a Democratic Senate, and showed a large majority for the Biden agenda.

Some of these goals could become more real as the final numbers post. But instead, at least for now, Democrats have an unsettled outcome, a real possibility of a second Trump term, and in that vacuum of uncertainty a president who immediately began sowing doubts about the final results, in a speech in the East Room at 2:30 a.m., and making threats to disenfranchise Americans.

In fairness, a lot of Biden advisers tried to tamp down expectations. A senior Biden adviser told me last week that the “path of least resistance” for a Biden victory was through Arizona, Michigan, Wisconsin, and the single electoral vote from Nebraska-2, a combination that wouldn’t require North Carolina, Georgia, Florida, or even Pennsylvania. It would be just enough for 270 electoral votes.

On Wednesday morning that appeared to be one of the more likely paths for Biden to become president: a bare victory, but victory nonetheless.