Madison Cawthorn invited a GOP candidate on the House floor in apparent violation of rules

Rep. Madison Cawthorn (R-NC) appears to have violated congressional rules by inviting a Republican candidate onto the U.S. House floor.

Republican lawmakers were surprised to see House candidate Robby Starbuck, of Tennessee, on the floor during votes Tuesday evening, and they told The Hill's Scott Wong the GOP hopeful had been invited there by Cawthorn.

"For a candidate for Congress to walk around on the floor and talk to people, I found it to be very bizarre," one GOP lawmaker said, adding it was "without a doubt" a violation of House rules unless the Sergeant at Arms gave him permission.

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According to House rules, only current and former members are allowed to step onto the floor, and sometimes staffers who are managing time.

Starbuck posted a photo of himself hours earlier with Cawthorn and Sen. Marsha Blackburn (R-TN) at the U.S. Capitol.