Stacy Keibler (WireImage)

Why is this man smiling?

Could be because his rumored girlfriend is “Dancing with the Stars” contestant Stacy Keibler, 31.

George Clooney, 50, stepped out with Keibler at his “Ides of March” premiere at the Toronto Film Festival last week. The duo didn’t walk the red carpet together but partied at Ritz-Carlton’s Deq bar.