Massachusetts State Sen. Scott Brown, R-Wrentham, celebrates with supporters in Boston earlier tonight, after winning a special election held to fill the U.S. Senate seat left vacant by the death of Sen. Edward Kennedy. (AP Photo/Charles Krupa)

In an epic upset in liberal Massachusetts, Republican Scott Brown rode a wave of voter anger to win the U.S. Senate seat held by the late Edward M. Kennedy for nearly half a century, leaving President Barack Obama's health care overhaul in doubt and marring the end of his first year in office. Addressing an exuberant victory celebration Tuesday night, Brown declared he was "ready to go to Washington without delay" as the crowd chanted, "Seat him now." Democrats indicated they would, deflating a budding controversy over whether they would try to block Brown long enough to complete congressional passage of the health care plan he has promised to oppose/Associated Press. More here.

Question: What does Brown's victory mean for the current political landscape?