Freshman Sen. Ted Cruz (R-TX) has attracted a lot of fans with his Joe McCarthy-like style, but Sen. John McCain (R-AZ) isn't one of them.

In fact, McCain "f*cking hates" the tea party darling, according to an adviser.

An October GQ profile of Cruz explains that tensions between Senate republicans boiled over earlier this year when Cruz participated in Sen. Rand Paul's (R-KY) filibuster of John Brennan's nomination to head the CIA over President Barack Obama's use of drones.

"He fucking hates Cruz," one McCain aide told the magazine. "He's just offended by his style."

At the time, McCain had publicly referred to Cruz and other Republicans as "wacko birds."

"If standing for liberty and standing for the Constitution makes you a wacko bird then I am a very, very proud wacko bird," Cruz later told CBS News.

And if McCain doesn't appreciate Cruz' style then the feeling seems to be mutual.

"I don't know a conservative who didn't feel embarrassed voting in 2006 or 2008," the Texas Republicans explained to GQ, referring to McCain's presidential bid. "I think the Republican Party lost its way. We didn't stand for the principles we're supposed to believe in."

(h/t: Talking Points Memo)