Democratic Sen. Jeanne Shaheen of New Hampshire will not seek reelection next year, a decision that will end the longtime senator’s historic political career and deals a significant blow to Democrats, who were already facing a difficult path to reclaiming the Senate majority.

Shaheen, who turned 78 in January, was the first woman elected to serve as both governor and senator in the United States. She announced her decision in a video posted on social media.

“Today, after careful consideration, I’m announcing that I have made the difficult decision not to seek reelection to the Senate in 2026,” she said. “It’s just time.”

History suggests that the GOP, as the party that controls the White House, would face a challenging political environment in next year’s midterm elections, which will decide the balance of power in Congress — and, with it, the fate of President Donald Trump’s legislative agenda. Republicans are also facing the possibility of serious economic headwinds as consumer pessimism grows and business leaders fret about Trump’s intensifying trade war.

But even before Shaheen’s announcement, the political landscape favored Republicans in the fight for the Senate, where the GOP already holds 53 seats compared with the Democrats’ 47, including two independents who caucus with Democrats.

Republicans now have pickup opportunities in three purple states where Democrats have announced retirements in recent weeks: New Hampshire’s Shaheen, Michigan Sen. Gary Peters and Minnesota Sen. Tina Smith. And the GOP is especially optimistic about the party’s chances in Georgia, where Democrat Sen. Jon Ossoff is expected to face a tough road to reelection.

Democrats, by contrast, don’t have any obvious pickup opportunities.

At least for now, Maine represents the Democrats’ best chance. Republican Sen. Susan Collins, the sole GOP senator remaining in New England, is the only Republican serving in a state Trump lost who’s up for reelection.

Republicans responded to Shaheen’s decision with glee.

“Another one!” Sen. Tim Scott of South Carolina, who leads the Senate Republican campaign arm, wrote on X. “Shaheen’s retirement is welcome news for Granite Staters eager for new leadership. New Hampshire has a proud tradition of electing common-sense Republicans — and will do so again in 2026!”