Texas Sen. John Cornyn is leading an early charge against President Barack Obama, seeking to blunt the new administration's momentum in Congress while lighting the way for a GOP comeback in the next election. "I think he has decided that the only chance Republicans have is to be very aggressive," political scientist Larry Sabato said of the Texan, who come to Washington six years ago as a defender of President George W. Bush. Cornyn said the campaign committee role makes him a key player in the Senate GOP leadership as well as the architect of the party’s Senate campaign in...