According to a report in the Huffington Post, Texas Rep. Louie Gohmert walked up to the line, then emphatically stepped over it on Friday while speaking at the Values Voter Summit.
Referring to "some senator from Arizona" (which we'll go ahead and guess isn't Sen. Jeff Flake), Gohmert described "a guy who liked Gaddafi before he wanted to bomb him, a guy who liked Mubarak before he wanted him out, a guy that's been to Syria and supported al-Qaida and the rebels."
McCain traveled to Syria in May to meet with rebels, becoming the highest U.S. official to do so since the country's civil war began. He has stated repeatedly that while supporting the rebels, he does not want the U.S. to support Islamic extremism. The group McCain met has been attacked by rebels loyal to Al Qaeda.
McCain spokesman Brian Rogers told HuffPost in an email that "Senator McCain wouldn’t dignify that with a response" when asked about Gohmert's statements.
Watch Gohmert here, via Right Wing Watch: