Rep. Todd Tiahrt (R-Kan.) joined the newly-founded Tea Party caucus late Tuesday in the hope of boosting his prospects in the GOP Senate primary.

The caucus, which was founded by Rep. Michele Bachmann (R-Minn.) as an "informal group" on July 15, is set to meet Wednesday for the first time.

Tiahrt trails Rep. Jerry Moran (R-Kan.) significantly in the race to succeed Sen. Sam Brownback (R-Kan.). In a SurveyUSA poll released Monday, 50 percent of respondents said they supported Moran and 36 percent backed Tiahrt.

"The Tea Party Caucus will help us amplify our message inside the halls of Congress and make sure the people’s voices are heard and not ignored by the Majority Party," Tiahrt said in a statement.

Moran also joined the caucus, but didn't announce his decision publicly because he's attending the funeral of his mother on Wednesday.

The group’s goal is to "promote Americans' call for fiscal responsibility, adherence to the Constitution, and limited government," Bachmann wrote in a letter to Rep. Robert Brady (D-Pa.), who chairs the House Administration Committee.

Since it was formed the caucus has attracted GOP Conference Chairman Mike Pence (Ind.), National Republican Congressional Committee Chairman Pete Sessions (Texas) and Reps. Paul Broun (R-Ga.) and John Carter (R-Texas), according to the House website. Fox News reported that Reps. Cliff Stearns (R-Fla.), Dan Burton (R-Ind.) and Pete Hoekstra (R-Mich.) also joined the caucus.

[Updated at 4:19 p.m. An earlier version of this post stated incorrectly that Moran hadn't joined the Tea Party caucus.]