Catalina Lauf, who served in the Department of Commerce under the Trump administration, launched a bid Thursday to oust Kinzinger from his seat in the 16th congressional district of Illinois.

“I never thought I’d primary a fellow Republican, but is Congressman Kinzinger really a Republican anymore? He isn’t and we have the proof,” the 27-year-old challenger said in a campaign announcement video.

Lauf said her 42-year-old opponent is a “weak-kneed, establishment Republican” who “cares more about his next MSNBC appearance than the voters who elected him.”

She claimed Kinzinger does not support the “America First” movement, noting his “one in three votes” in Congress that have sided with House speaker Nancy Pelosi (D., Calif.)