"I'm just sick of it all," said Bette Carlson, who showed up to hear Gingrich speak at Mabe's Pizza in Decorah, Iowa, Tuesday night. "Anyone who stays out of the mud improves their chances of getting my vote."
Still, the Gingrich camp maintains it is giving the pledge more than just lip service. They note an Iowa staffer had to resign after calling Mormonism — Romney's religion — a cult.
And Gingrich argues he has enough cash to run a negative ad war if he wanted to. He notes his campaign made the choice to run positive ads across Iowa beginning Wednesday.
Still, Gingrich might know better than most this election cycle that negative ads work.
He has seen his support slide as the airwaves in Iowa have filled with ads reminding voters of his ethics woes, a public service announcement he shot with Democrat Nancy Pelosi and his lucrative work for Freddie Mac.
The libertarian-leaning Paul has assailed Gingrich for "serial hypocrisy," painting him as a career politician who lined his pockets after leaving office by selling access.
In an interview, Romney called him "zany."
How long can Gingrich keep up the positive façade? Asked if he would he would continue the commitment in a general election against Democrat Barack Obama, Gingrich dodged the question.
"Barack Obama's record is so terrible that if you just tell the truth it sounds negative," Gingrich said.
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