 On September 12 , 2009 ( his 50th birthday ) , Brown announced his run for the U.S. Senate seat that became vacant with the death of Ted Kennedy , saying the state " needs an independent thinker . " Washington Post columnist Kathleen Parker said that Brown 's political positions did not fall neatly into party lines , and called Brown " mainstream in a nation that defines itself as mostly conservative . " Boris Shor , political scientist at the Harris School of Public Policy , described Brown as a liberal Republican by national standards , but well @-@ suited for his Massachusetts constituency . Shor explained the support Brown was receiving from the conservative national GOP as due to their " decentralized decision " to support the candidate most likely to win . 
