Republican Greg Gianforte overcame an election eve assault charge filed against him that sparked national attention, defeating Democrat Rob Quist in the race for Montana’s open U.S. House seat Thursday.

Gianforte received 50.7 percent to Quist’s 43.5 percent with 97 percent of precincts reporting late Thursday. Libertarian Mark Wicks picked up 5.8 percent of the vote.

The result is a major disappointment for progressive activists who poured money into the campaign to help Quist, a banjo-playing songwriter and political newcomer, in a bid to notch a symbolically important win against President Donald Trump.

“Your voices were definitely heard in this election,” Quist told supporters after the results were final. “I know we came up short, but the energy in the state and the grassroots movement in the state goes on.”

The defeat is especially demoralizing for Democrats in light of the misdemeanor assault charge against Gianforte, a multimillionaire tech entrepreneur and social conservative, for allegedly “body slamming” Ben Jacobs of The Guardian on Wednesday while the reporter was asking about the GOP health care bill. Gianforte’s campaign blamed Jacobs, casting him as a “liberal reporter” who acted “aggressively” toward the Republican as he was about to be interviewed by a TV crew. But Alicia Acuna, the Fox News reporter who was slated to interview Gianforte, corroborated Jacobs’ version of events, and the incident spurred widespread condemnation of the Republican.

“Last night I made a mistake,” Gianforte said in his victory speech Thursday night. “I should not have responded in the way that I did, and for that I’m sorry.”