A person who sits by while another person tries to accomplish something.
President Obama made the reference when talking about Republicans. Said Obama: "We're down there. It's hot. We were sweating. Bugs everywhere. We're down there pushing, pushing, pushing on the car. Every once in a while we'd look up and see the Republicans standing there. They're just standing there fanning themselves -- sipping on a Slurpee."
Newt Gingrich: We need to cut taxes, reduce budget deficit, protect the Constitution, blah, blah, blah....
President Obama: Quit being a slurpee sipper and help us out here!