Eastwood defends RNC empty-chair speech

>>> clint eastwood spoke out for the first time since the speech at the gop convention last week. those who watched felt as if he was making something up on the fly. it turns out that's pretty much what happened. our report tonight from nbc's andrea mitchell .

>> reporter: a week later at the democratic convention , clint eastwood 's chair was still getting laughs.

>> i know it's an iffy chair. it makes you nervous, doesn't it. that's all right. i'm going to sit on it.

>> what do you mean shut up?

>> reporter: it was a rambling, unscripted appearance at the republican convention that went more than twice as long as it should have. it went viral. eastwood immediately started trending on twitter. mitt romney 's top aides acknowledged they didn't know what eastwood would say, unheard of at a national political convention , where speakers are timed to the second.

>> i know what you're thinking.

>> reporter: now eastwood has tony told his hometown newspaper they vet most of the people, but i told them you can't do that with me because i don't know what i'm going to say. he said the idea of interviewing an imaginary president obama in an empty chair came at the last moment when a stagehand kept asking him if he wanted to sit down. inspiration struck as he was walking out on stage, telling the paper, "when i saw the stool sitting there, it gave me the idea. i'll just put the stool out, there and i'll talk to mr. obama and ask him why he didn't keep all of the promises he made to everybody."

>> so mr. president, how do you handle -- how do you handle promises that you have made?

>> reporter: a peer survey cited eastwood 's speech as the republican convention 's top highlight, beating out mitt romney 's speech. now like eastwood 's movies, his empty chair has found its place in pop culture . andrea mitchell , nbc news, washington.