Defiant Herman Cain says he won't drop out of race; Mitt Romney says to address allegations

But they're untrue, he declared.

Other Republicans sounded alarms about Cain's troubles and the impact on the GOP race as the party gears up to try to defeat President Barack Obama next fall.

"Get all the facts in front of people, otherwise he's going to have this continuing distraction," Mississippi Gov. Haley Barbour, a former Republican National Committee chairman with deep ties to the GOP establishment, told MSNBC.

Though recent polling shows Cain still doing well, party operatives suggested it was only a matter of time before his political standing could suffer.

"Herman's base is going to stick with him," said Republican strategist Rick Tyler, Newt Gingrich's former spokesman. "But the average Republican voter who is not as engaged as intensely in the race, is sick of this and, for Cain, the concern is they will pass on it and pass on him."

Cain looked to keep those supporters in his corner.

"We are not going to allow Washington or politics to deny me the opportunity to represent this great nation," he said.

"As far as these accusations causing me to back off and maybe withdraw from this presidential primary race? Ain't gonna happen. Because I'm doing this for the American people, and the children and the grandchildren."

McCaffrey reported from Atlanta. Associated Press writers David Espo in Washington and Becky Bohrer in Alaska contributed.

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