Democratic Sen. Jon Tester of Montana has lost re-election to businessman Tim Sheehy, NBC News projects.

The rare Democrat representing a red state, Tester served three terms after establishing a reputation as a moderate Democrat with long ties to Montana. But his folksy persona, which includes a flat-top haircut and three missing fingers from a childhood meat-grinder accident, was not enough to overcome the strong partisan headwinds of a divisive presidential election that landed Donald Trump back in the White House, as split-ticket voting has become less common in American politics.

Sheehy, a Minnesota native who moved to Montana to start an aerial firefighting company, was endorsed by Trump in the Republican primary, which led his main opponent, Republican Rep. Matt Rosendale, to drop out shortly afterward.

Trump also campaigned for Sheehy in August, a rare stop in a state with four electors that has gone for the Republican presidential nominee since 1996. The campaign stop seems to have worked, however, with polls showing Sheehy pulling ahead around that time, despite questions about his claim that he was shot in Afghanistan.

Sheehy also seems to have benefited from Montana’s shifting political environment, which has become increasingly nationalized and has put moderates from both parties on the back foot. Tester’s advantage as a Montana native and former state legislative leader weren’t enough to cut through the national partisanship.

Tester was one of a handful of senators whose states reliably vote for the presidential nominee of the other party, along with retiring Sen. Joe Manchin of West Virginia, a former Democrat who is now registered as an independent, and Republican Sen. Susan Collins of Maine. The loss means Democrats will have an even harder time winning control of the Senate in future elections.

This is a developing story. Check back for updates.