State Rep. Joe Carr will challenge Tennessee Sen. Lamar Alexander in next year’s Republican primary. He announced his campaign on Tuesday in front of a banner that misspelled the word “Senate.”

His campaign released the “Carr for US Sentate” image, then fixed the spelling.

In an interview with WTN-FM radio, Carr said he decided to mount a Tea Party challenge for the Republican nomination because he considers Sen. Alexander “the most liberal member of the delegation from Tennessee.”

Soon after the announcement, Carr’s top campaign aide, Chip Saltsman, handed in his resignation and said he would join Alexander’s re-election campaign. “It is because of Lamar Alexander that people like you have the honor of serving in the majority of the state legislature,” Saltsman wrote in his resignation letter. ”It is because of Lamar Alexander that our children and grandchildren go to better schools, and are able to compete for better jobs. It is because of Lamar Alexander that we live in a state people want to move to, start a family in, start a business in, and even retire to. I am honored to support Lamar Alexander for re-election.”