Santorum's Michigan Mojo Spreads Nationally (Update 1)

Updated from 12:16 p.m. with latest national Republican primary race polls

NEW YORK ( TheStreet) -- Rick Santorum grabbed a lead Monday in a Michigan primary poll and then took the national lead in surveys, a shift that may signal an ongoing reversal in momentum for Mitt Romney.

Santorum's new 15 percentage-point lead in a Public Policy Polling survey against Romney in Michigan -- where front-runner Romney's dad was once the state's governor -- showed a 30 percentage-point swing in voter sentiment since the last polls were released some 10 days ago.

"Rick Santorum has all the momentum in Michigan right now," Dean Debnam, Public Policy Polling president, said in a statement. "But it's important to note that more than 50% of voters say they could change their minds in the next two weeks."

Romney's campaign has its work cut out as it fell behind Santorum in a Pew Research national GOP poll that showed the former senator ahead of Romney 30% to 28%.

It is important to note a Gallup poll also released Monday showed Romney ahead of Santorum 32% to 30%. But the Pew poll gave Santorum the lead in an aggregate of national polls 30.3% to 29% against Romney, while Newt Gingrich sits in third at 20% and Ron Paul is back in fourth at 12%.

Debnam said there was plenty of room for Romney to shift the race back in his favor before voters headed to the polls on Feb. 28.

Michigan seemed firmly in Romney's favor as the presidential candidate grew up in the state and has significant campaign organization and ties there, and the prospect of Santorum grabbing the lead in the national polls seemed unimaginable a week ago. But Santorum's surprise series of victories last Tuesday showed the former Pennsylvania senator had gathered steam as the Romney-alternative among conservative Republicans.

Santorum leads Romney 39% to 24% in the Michigan poll while Ron Paul and Newt Gingrich trailed with 12% and 11% shares respectively.

-- Written by Joe Deaux in New York.

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