The 2010 TIME 100

People love a David-vs.-Goliath story. That is to say, they love David, the underdog who whips a bigger foe thought to be indomitable. Little-known Scott Brown, 50, took on President Obama and an entrenched political machine in Massachusetts, and against all the nay-saying, he won. Not even a last-minute visit from the President could stop it from happening — and the aftershocks are still being felt. There has been much speculation about the cause of his upset: unrest over the Obama tax-and-spend agenda, a weak opponent, concern about an expanded federal role in health care. But if ever there was a person who willed himself to win, it was Scott. In the early going, when the media and even his own party had given up on him, Scott never gave up on himself. The Republican long shot tossed a sign into the back of his now famous truck and drove to heavily Democratic South Boston, where he stood by himself in front of McGoo's Pizzeria on West Broadway and passed out campaign brochures. As the returns came rolling in on Election Day, the course of American politics was changed.

Romney is a former governor of Massachusetts

TIME 100 Social-Networking Index: 131,053