When Will We Know Who Controls US Congress?

The stakes in Tuesday's election — control of Congress — are crystal clear. But it's not clear when that will be known in its entirety.

The Associated Press is calling races in all 435 House districts and the 35 Senate contests that are up for election this year.

Control of the House depends on which party reaches 218 seats. Currently, 219 members caucus with Republicans, one more than the minimum needed for a majority when all seats are filled. There are two vacancies now.

Democrats took back the 100-member Senate in a flurry of victories late Tuesday.

It was a far quicker outcome than during the last midterm elections in 2022, when the AP called control of the Senate four days after Election Day. The House call was eight days after.

During the presidential cycle of 2024, there was a bigger gap between the two. Senate control was called the day after Election Day, with the House call coming eight days later.

Some states consistently take days to count all their ballots. California, the nation's most populous, has seen thousands of mail ballots dropped off on Election Day. In 2022, half the state's votes were counted after Election Day.

Other states such as Alaska and Maine, which had key Senate races this year, use ranked choice voting.

A candidate can win with more than 50% of votes in the first round, but if no one reaches that threshold then the candidate with the fewest first-choice votes is eliminated and their votes are redistributed to the voter's second choice. The process can significantly delay results.

The AP does not make projections and will only declare a winner when it's determined there is no scenario that would allow the trailing candidates to close the gap.

(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)