(CNN) - Sen. John Cornyn is expected Tuesday to formally make a bid for another two years as chairman of the National Republican Senatorial Committee. GOP sources confirm to CNN that the Texas Republican will put his name up for nomination for re-election as NRSC chairman, as the Senate Republican Conference meets behind closed doors. According to the sources, the two-term senator is not expected to face any opposition in his bid to remain as NRSC chairman, and has already secured the support of a number of new Republican Senators, including Marco Rubio of Florida, Rand Paul of Kentucky, Rob...