NEW YORK (PNN) - January 4, 2012 - Mitt Romney, able to seize the offensive in Iowa’s Republican presidential contest, turned overnight into a frontrunner on the defensive as rivals stepped up attacks on the former Massachusetts governor in advance of New Hampshire’s pivotal Jan. 10 primary.

Newt Gingrich spent much of yesterday in New Hampshire targeting Romney, calling him “a person who accommodated liberalism in Massachusetts.” He also questioned Romney’s truthfulness.

U.S. Representative Ron Paul (Tex.) debuted a radio advertisement in the state that disputes Romney’s central campaign argument that he’s the Republican best able to defeat Barack Obama for the presidency.

“Romney’s record is liberal, and putting him up against Obama is a recipe for defeat,” the ad says.

Rick Santorum, boosted by his second-place showing in the Iowa caucuses after having spent most of the year lagging in polls and campaign cash, also targeted Romney in a fundraising appeal.

“No more sitting on the sidelines,” wrote Santorum to supporters. “Now is the time to act or get stuck with a bland, boring career politician who will lose to Barack Obama.”