The third-ranking GOP House leader is the third prominent elected Republican to voice his support for the former Massachusetts governor since last week. Former Florida Gov. Jeb Bush endorsed Romney on Wednesday, and tea party favorite Sen. Jim DeMint, although he did not outright endorse the candidate, said he was “excited” about the frontrunner on Thursday.
McCarthy also joins House Majority Leader Eric Cantor, R-Va., in his support of the former Massachusetts governor. Cantor endorsed Romney earlier this month ahead of Virginia's primary.
News of McCarthy's endorsement comes as another tea party stalwart, Sen. Mike Lee, R-Utah, announced that he would also endorse Romney. According to the Salt Lake Tribune, Romney welcomed Lee's endorsement on Sunday. Lee becomes the last of the Utah congressional delegation to back Romney's bid.
Matt Vasilogambros contributed contributed to this article.