Santorum surges ahead in polls

Rick Santorum's drive to capture the Republican presidential nomination gained momentum Tuesday as he surged to the front of the field in national polls and extended his lead over Mitt Romney in his rival's native Michigan.
But Romney's supporters were just rolling out the big guns -- massive spending on television and radio ads -- that drove previous poorly funded challengers from the field in key states like Florida and Iowa.
Michigan, where Romney was born and raised, is looming as a crucial, must-win state for the candidate, who has struggled to convince Republicans he is the man to go up against President Barack Obama in November elections.
But national polls showed Santorum surging ahead of longtime frontrunner Romney and the ground shifting rapidly against the former Massachusetts governor since he lost three state nominating contests to the former Pennsylvania senator last week.
A national CBS/New York Times poll released Tuesday had Santorum at 30 percent among likely Republican primary voters, to 27 percent for Romney, Paul at 12 percent, and Gingrich at 10 percent.
In Michigan, Santorum is now out front at 39 percent to 24 percent for Romney, 12 for libertarian Paul and 11 percent for Gingrich in a survey released Monday by Public Policy Polling.