In a mostly Democratic state, he beat Attorney General Martha Coakeley to replace the late Ted Kennedy. Tea Party groups gave him support. However, "when told that at various times he has been labeled a conservative, moderate and a liberal Republican, he responded 'I'm a Scott Brown Republican.' According to Politifact, while Brown was a Massachusetts legislator, he voted about 90 percent with the state Republican leadership; however, Republican Leadership in the Massachusetts legislature is generally considered far more moderate than the national Republican Party."
He has praised some Democratic senators and said he is willing to work across party lines and has taken positions "at odds with some of his fellow Republicans and Tea Party conservatives" as well as "Glenn Beck other prominent conservatives."
"According to the Washington Post, Brown voted with the majority of Republicans 80% of the time. In the same poll, '56% of Massachusetts voters believed he has kept his promise to be an independent voice in the U.S. Senate.'"
As a pre-1980 John Anderson Republican, I think it's great to see that not all Republicans are Roboticans.
Quotes are from en.wikipedia.org/wiki/Scott_brown.
