Sen. John McCain asked former pro-Basketball player and TNT analyst Charles Barkley to join him in a bet via Twitter on Monday.

@SenJohnMcCain tweeted, "Dear Charles Barkley, 'don't take it personally, you seem like a nice guy,' but you're clueless - @MittRomney wins. Wanna bet?"

The suggested bet appears to be in response to comments Barkley made during a broadcast Sunday night, when he saw Mitt Romney in the crowd at a Boston Celtics game. The Celtics beat the Atlanta Hawks.

"We're going to beat you like a drum in November. Don't take it personally. I like you. You seem like a nice guy, but you're going down, bro," said Barkley on the air when Romney turned up on camera.

Barkley has not publicly responded to McCain's invitation.