Midterm control calls may lag behind voting

American voters will cast ballots Tuesday to determine the composition of the next Congress, yet the timeline for confirming which party holds the majority could extend beyond Election Day.

The Associated Press plans to adjudicate all 435 House districts and 35 Senate contests. In the lower chamber, the Republican caucus currently holds 219 seats, giving them a one-seat advantage over the 218 required for a majority. Two vacancies currently exist in the House. In the upper chamber, Democrats need 51 seats to claim control, while Republicans require 50 because Vice President JD Vance retains the tie-breaking vote. Republicans presently hold a 53-47 margin in the Senate.

Past results indicate that determining congressional leadership is a slow process. In the 2022 midterm cycle, the AP confirmed Senate control four days after voting concluded. The House majority was not officially recognized until eight days later. The 2024 presidential election showed a similar pattern, with the Senate decided the day after the election and the House following eight days after.

Specific state election mechanics contribute to these delays. California, the nation's most populous state, relies heavily on mail ballots. In 2022, half of the state's total votes were processed after Election Day. Additionally, Alaska and Maine, which feature critical Senate races this year, utilize ranked choice voting. This system can prolong results if no candidate secures more than 50 percent of first-choice votes, necessitating the elimination and redistribution of ballots to second choices.

The AP adheres to a strict standard for declaring winners. It does not issue projections and will only announce a result when no mathematical scenario allows a trailing candidate to close the gap.