The chairman of the Montana Republican Party slammed Sen. Jon Tester (D-MT) on Wednesday for calling attendees at Vice President Mike Pence’s rally “fake Montanans.”

Sen. Tester’s campaign released a statement on Tuesday regarding Vice President Pence’s rally for Montana Senate Republican candidate and state auditor Matt Rosendale.

Luke Jackson, a campaign spokesman for Tester, said, “Maybe next time Vice President Pence comes to Montana he can spend some time meeting with real Montanans instead of swooping in to try to save Rosendale’s fledgling campaign.”

Debra Lamm, the chairman of the Montana Republican party, called on Tester to apologize to Montana Trump supporters.

“Just because people here disagree with Jon Tester doesn’t make them fake Montanans,” Lamm said.

“This is a disgusting display of partisanship by Tester’s campaign. Over 400 Montanans showed up at the rally to listen to the Vice President of the United States, and these Montanans care about our Constitution, gun rights, and securing the border – issues Tester could care less about,” Lamm continued. “So, Tester needs to man up and do what’s right and apologize to all the good Montana folks in attendance yesterday at the rally with the Vice President.”

Sen. Tester announced last week he will oppose Supreme Court Justice nominee Brett Kavanaugh’s nomination due to his alleged opinions on privacy, campaign finance reforms, and the allegations that Kavanaugh sexually assaulted California psychology professor Christine Blasey Ford.

Pence said Tester is “voting against Judge Kavanaugh because he’s a conservative.” He added, “I’m going to tell you, I think Montana deserves better.”

The Montana Senate race has become increasingly competitive. A poll released in September found that Tester and Rosendale are in a virtual tie at 44 percent each. Given that a majority of Montanans approve of Trump and that the president won the state by 20 points in the 2016 presidential election, Tester’s opposition to Kavanaugh will only make the race more competitive.

After Tester announced he will oppose Kavanaugh for the Supreme Court, Rosendale contended that this proves yet again that Tester has sided with Senate Minority Leader Chuck Schumer (D-NY) over Montana.

“We can’t trust Jon Tester on the Second Amendment. If you support President Trump and want to protect our Second Amendment Rights then the choice is clear this November,” Rosendale added.