The president was in Boulder as part of a tour of college campuses intended to pressure Congress to take action to prevent an automatic increase in higher education loan rates this summer.
During an unannounced stop at The Sink at about 6:25 MDT, Obama shook hands, posed for pictures, ordered a large pizza and bought a stack of T-shirts. As the president greeted a cluster of people outside the restaurant, a young woman spilled yogurt on him.
Obama wiped up the spill with a towel and told the woman, "Getting yogurt on the president, you've got a story to tell."
"I'm very embarrassed," the young woman said.