Republican Arizona Sen. John McCain’s characterization of conservative Republican legislators as “wacko birds” has set off a social media firestorm replete with a surging #wackobirds Twitter hashtag and a new genre of “wacko birds”-inspired Internet artwork.

In an interview last week with the Huffington Post after Republican Kentucky Sen. Rand Paul’s 13-hour filibuster of CIA nominee John Brennan, McCain referred to Paul, Republican Texas Sen. Ted Cruz and Republican Michigan Rep. Justin Amash as “wacko birds.”

“They were elected, nobody believes that there was a corrupt election, anything else,” McCain said. “But I also think that when, you know, it’s always the wacko birds on right and left that get the media megaphone.”

Since McCain’s remark, Amash has been using his Twitter account to help boost the growing #wackobirds hashtag, which numerous conservatives and libertarians have latched onto to proclaim themselves fellow “wacko birds.”

Many users have also switched their Twitter names to incorporate the term “Wackobird,” including “Wackobird Amy,” “Wacko Bird Jones” and “WackoBird Mike.” One new Twitter account called “WackoBird” declares that it was “hatched from the minds of RINO’s,” which stands for Republicans in Name Only, while another promises “official tweets from Republican Wacko Birds.”

Amash also retweeted a graphic posted by the group Young Americans for Liberty depicting Amash, Cruz and Paul as “wacko birds” and McCain as a pig trying to blow their house down — a reference to the popular “Angry Birds” game franchise.

An image posted to the #Wackobirds hashtag depicts McCain and South Carolina Republican Sen. Lindsey Graham imploring Revolutionary War-era statesman Patrick Henry to “calm down” and calling him “unprofessional” during his famous “Give me liberty or give me death”-speech to Virginia’s House of Burgesses.

Another user-generated work of art portrays a video game battle between Paul and McCain.

Numerous Twitter users linked the image of “wacko birds” to soaring American bald eagles, with one graphic asking, “Senator McCain, are these the wackobirds?”

McCain’s “wacko birds” remark coincided with an historic social-media outpouring of support for Paul’s filibuster, in which Cruz, Florida Republican Sen. Marco Rubio and other Republican and Democratic senators participated. The filibuster — launched to protest the Obama administration’s initial refusal to disavow the authority to use a drone to kill an American citizen on U.S. soil — made the Twitter hashtag #StandWithRand trend nationally. Cruz mentioned the hashtag in his remarks on the Senate floor during the filibuster.

McCain sharply criticized Paul’s filibuster during a speech on the Senate floor, declaring that he didn’t “think that what happened yesterday was helpful to the American people.”

McCain’s “wacko birds” dismissed the senator’s criticism.

“I take that as a badge of honor,” Cruz told a Miami Herald reporter, referring to McCain’s jab.

Paul offered a more serious response to McCain’s attack.

“I treat Sen. McCain with respect. I don’t think I always get the same in return,” Paul said.

McCain, for his part, complained on liberal CNN host Piers Morgan’s program, “Well, you know, I am always intrigued by the fact that when I disagree with my own party leadership, my own president — like saying that Donald Rumsfeld ought to resign, [or] we need to do the surge — then I’m a brave maverick. When I’m taking on others, then he’s just an angry old man.”

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