In their bid to keep control of the Senate this November, Republicans are setting their sights on a pair of unlikely foes: singer-songwriter Ben Folds and country rocker Jason Isbell.

The musicians are set to headline a rally Monday night for former Tennesse governor Phil Bredesen (D), who is facing off against Rep. Marsha Blackburn (R) in one of the country’s most closely watched Senate races.

On Monday afternoon, the National Republican Senatorial Committee sent out a tweet about the rally claiming that Bredesen is “part of the unhinged, angry left and supports people who vehemently oppose President Trump.”

“Despite Bredesen’s moderate act, he continues to embrace people who have made it a habit of insulting the Tennessee voters who proudly supported President Trump,” NRSC spokesman Michael McAdams said in a statement on the event. “Today’s fundraiser is the latest example that Phil Bredesen is completely out-of-touch with a majority of Tennesseans.”

In a statement, Bredesen’s communications director, Laura Zapata, called Isbell “a champion for working men and women” and described Folds as “a leading advocate for arts education.” She also pointed to a performance by Folds during a panel on the arts at the 2016 Republican National Convention.

“The swamp needs to spend less time worrying about these popular recording artists and more time looking into Marsha Blackburn’s ties to hate groups and Russian nationals, and her illegal coordination with dark-money groups in Washington,” Zapata said.

Folds, who supported Sen. Bernie Sanders (I-Vt.) for president in 2016, is best known for his catchy pop tunes and virtuosic piano playing as the leader of the band Ben Folds Five, formed in the early 1990s. More recently, Folds has been a prominent arts education advocate and last year was named an artistic adviser to the National Symphony Orchestra.

Isbell, a former member of the band Drive-By Truckers who has since launched a solo career, won Best Americana Album and Best American Roots Song at this year’s Grammy Awards.

He has at times had sharp criticism for Trump and his supporters. On Monday, the NRSC seized on a Rolling Stone interview last year in which Isbell said of conservative Christians who back Trump, “God is gone from those people.”

Isbell responded on Monday with a tweet linking to a story about the dust-up over his appearance at the Bredesen event.

“I’ve been in the paper a few times now, but this one is my favorite,” Isbell said. “This is one I’ll be proud to show my grandkids.”

The incident is only the latest in which musicians have become caught in the political crossfire.

Last week, the NRSC voiced outrage over an apocalyptic poster promoting a Pearl Jam concert that was used to raise money for Sen. Jon Tester’s (D-Mont.) reelection bid. Tester’s campaign said it did not approve of the design of the poster, which depicted an eagle picking at the carcass of a dead Trump outside of a White House engulfed in flames.

John Wagner contributed to this report.