Updated October 26, 2026.
Republicans hold a 53-47 Senate majority, and 35 seats are on the ballot on November 3. A handful of tight contests are expected to decide control of the chamber. Here is a summary of the races drawing the most attention, based on reporting from ABC News.
Texas
Texas Attorney General Ken Paxton defeated longtime Sen. John Cornyn in a costly Republican primary runoff after receiving a late endorsement from President Trump. ABC reports that many Republicans view Paxton, a hardliner and Trump ally, as a harder sell to general-election voters than Cornyn would have been. That has given Democrats an opening in a state they have not won statewide in decades.
Alaska
Republican Sen. Dan Sullivan faces former Democratic Rep. Mary Peltola, and a second candidate who shares the senator’s name is also on the ballot. ABC rates the race a tossup. We explain how the state’s system works in our Alaska Senate race explainer.
Iowa
ABC also rates Iowa a tossup and describes the race as surprisingly competitive in a state that has trended Republican in recent cycles.
Maine
In Maine, the question is whether a campaign of roughly 100 days can unseat a long-serving incumbent, according to ABC.
Michigan
Former Republican Rep. Mike Rogers is locked in a tight race with Democrat Abdul El-Sayed, who has strong backing from the party’s progressive wing. Michigan has voted for Trump in two of the last three presidential elections, yet Democrats have won every Senate race there since 1994. ABC reports that Rogers is making inroads with some traditionally Democratic Jewish and Black voters who are wary of El-Sayed. Trump campaigned for Rogers on Sunday, and Barack Obama campaigned for El-Sayed in Detroit over the weekend.
The math
With 47 seats, Democrats need a net gain of four seats to reach 51. A net Democratic gain of three would produce a 50-50 split, which Republicans would control through the vice president’s tiebreaking vote. Each of the races above could matter, which is why both parties are spending heavily in the final days.
