Well John McCain bought me coffee last August.
We were both trying to get out of D.C. on Northwest - he was headed to Iowa and was standing behind me in line - paid for my coffee when I couldn't get my wallet out fast enough. He's much shorter in person. I just said "Thanks", shook his hand and headed back to my gate. Oddly enough, people were just ingoring him. Of course it was Reagan National and way back in August before things heated up in the campaign.
I will still hold my nose when I vote for him though. Respect the man and his service and sacrifice but hate a lot of his politics.