The decision by the Maryland Democrat, who has served in Congress for four decades — two of them in leadership — reflected a generational and demographic shift afoot in his party.
The vote would send the legislation back to the House, which is expected to approve it and send it to President Biden.
Democrats made the same-sex marriage bill one of their first major agenda items in the postelection session, moving quickly to enact it while their party still controls both chambers.
With Democrats on the cusp of losing the House, all eyes are on Speaker Nancy Pelosi’s next move, and the party is frozen in place until she decides what to do.
Marie Gluesenkamp Perez, an auto shop owner, defeated the Republican Joe Kent, a former Green Beret and combat veteran who denied the legitimacy of the 2020 election and backed Jan. 6 defendants.
With many races unresolved, the top House Republican rushed to declare victory and alert his colleagues that he still meant to seek the top post, even as he toiled to shore up his right flank.
Even with control of the House undecided, Kevin McCarthy, Republican of California, announced his bid in a letter to his colleagues.
The two-term Democrat had one of the tightest re-election battles in the House, but the victory of a hard-right election denier in the Republican primary helped boost his chances.
The two-term Republican defeated Representative Val Demings, a Democrat who would have been the state’s first Black senator.
The former president said that, if he runs for president and wins in 2024, Senator Mitch McConnell will “be out in two minutes.”