Republican Senate candidates have bounced back in two largely overlooked states, strengthening their party's chance to retain control of the U.S. Senate in Tuesday's elections, according to an exclusive series of McClatchy Newspapers-MSNBC polls. Twelve new state-by-state polls show a surprise shift in the political battleground to the north as Republican incumbents clawed their way back in two states frequently written off as lost to them -- Montana and Rhode Island. In Montana, Republican Sen. Conrad Burns has fought back to a 47-47 percent tie with Democrat Jon Tester after trailing in all earlier polls.