Republicans will maintain control of the Senate, but it is still unclear by how narrow a margin.

The Associated Press projects the chamber will remain in Republican hands, with a Democratic takeover blocked after losses in Indiana and North Dakota. Things got worse for Democrats later in the night when they lost Missouri, too. 

Retaining control of the Senate ensures Republicans will be able to continue confirming President Donald Trump’s judicial nominees, but advancing some of his policy priorities might run into complications with the House flipping to the Democrats on Tuesday night. 

Democrats always faced daunting odds of winning the Senate. They had 26 seats to defend — 10 of which were in states President Donald Trump won in 2016 — compared to only nine that Republicans had to defend. To win the majority, Democrats would have had to have held all 10 of those seats in Trump states, plus flip two GOP-held seats. 

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Given that Senate math, Trump had an outsize impact on the race for the Senate, barnstorming red states in the final days of the campaign to rally the GOP base.

Republican momentum picked up in several states heading into the homestretch. In Indiana, for example, Democratic Sen. Joe Donnelly appeared to have the upper hand after the primaries, while GOP nominee Mike Braun’s campaign faltered. But the race tightened this fall, and Braun ultimately defeated Donnelly on Tuesday night.

Likewise, the Missouri Senate race shifted in Republicans’ favor in the last few weeks of the race. Attorney General Josh Hawley defeated Democratic Sen. Claire McCaskill. He made the fight for conservative judicial nominees a central part of his campaign. 

In North Dakota, Democratic Sen. Sen. Heidi Heitkamp struggled to hold on in an increasingly Republican state that backed Trump by 36 points. Voters had previously supported both her and GOP Rep. Kevin Cramer, who also came to Washington in 2012, but they had to choose this year. Despite raising millions of dollars late in the race after voting against Supreme Court Justice Brett M. Kavanaugh, Heitkamp remained at a disadvantage in this conservative state. Cramer beat her easily Tuesday night.

At the Senate level at least, the heated confirmation fight over Kavanaugh seems to have worked in Republicans’ favor. Republicans said the episode energized their voters, while other strategists noted the late tightening in several of these Senate races was reflective of these states’ Republican lean and GOP voters naturally tuning in late.

The fight over Kavanaugh — and the way it nationalized these races — may have also boosted Tennessee Rep. Marsha Blackburn who defeated Phil Bredesen, a popular former governor, to fill the open seat being vacated by Sen. Bob Corker.

Not all Republican candidates were able to replicate Trump’s success, though. In West Virginia, for example, Democratic Sen. Joe Manchin III held on in a state Trump carried by 42 points. The only Democrat who voted to support Kavanaugh, he defeated state Attorney General Patrick Morrisey, who struggled against the former two-term governor. 

The party divide in the Senate is expected to remain close in part because Republicans could couldn’t put all of Trump’s 2016 states in play. In Ohio and Pennsylvania — two states that held expensive Senate contests in 2016 — GOP contenders struggled to gain momentum. Inside Elections with Nathan L. Gonzales moved both races to Solid Democratic before Election Day, and the AP quickly called the races for Democratic Sens. Sherrod Brown and Bob Casey.  Democrats also won easily in Michigan and Wisconsin, two states that Trump won in 2016 but that never materialized into competitive Senate contests. 

Bridget Bowman contributed to this report.