WASHINGTON - Newt Gingrich's campaign defections are just the latest tremor in a constantly shifting GOP presidential landscape that craves some steadiness as a big, early New Hampshire debate nears.

Rivals already were trying to poach Gingrich's donors and top supporters Friday, even as the former House speaker said he would keep campaigning despite the resignations Thursday of his top advisers and entire Iowa paid staff. Party insiders eyed the likely entry of Rep. Michele Bachmann of Minnesota and a possible bid by Texas Gov. Rick Perry.

Mitt Romney's decision to skip the Iowa straw poll in August reinforced the former Massachusetts governor's image as a front-runner willing to pick his shots. And potential candidate Sarah Palin again lent a circus atmosphere to the entire GOP family - this time indirectly - when Alaska released thousands of pages of e-mail messages from her days as governor.

In short, it was a typical week in the GOP's freewheeling nominating process. The field is anything but set, and there's no clear picture of who will emerge to challenge President Obama in 2012.

Gingrich spoke publicly Friday for the first time after his top aides' mass resignation. Several of them said they were frustrated because he was devoting insufficient time to the nitty-gritty work of meeting and galvanizing supporters in early voting states such as Iowa.

Gingrich said outside his suburban Virginia home that he was committed to campaigning "very intensely" for the White House. He attributed his aides' departure to disagreements about strategy. "We'll find out over the next year who's right," he said.

Gingrich received a vote of confidence from at least one high-profile backer: Georgia Gov. Nathan Deal, his campaign chairman in his old home state. "When the going gets rough, I don't cut and run on my friends," Deal said.

But Deal's predecessor, Sonny Perdue, who had been a national cochair for the Gingrich campaign, jumped to the campaign of former Minnesota Gov. Tim Pawlenty.

Pawlenty also picked up support from Al Hubbard, who directed the National Economic Council under President George W. Bush.

Republicans hoped the campaign focus might shift toward policy, and to what they consider Obama's shortcomings, on Monday evening, when seven Republicans will debate in Manchester, N.H.

Joining Romney, Pawlenty, Gingrich, and Bachmann will be Texas Rep. Ron Paul, former Pennsylvania Sen. Rick Santorum, and former pizza-company executive Herman Cain.

Notably absent will be former Utah Gov. Jon Huntsman, who has been campaigning unofficially for several weeks, mostly in New Hampshire. His aides said Huntsman would not enter debates until he formally announces his presidential plans.

Skipping the debate poses some risk for Huntsman, who recently stepped down as ambassador to China. He is virtually ignoring Iowa and needs to do well in New Hampshire if he runs, strategists say.