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Former House Speaker Newt Gingrich is moving to revive his presidential campaign, unveiling a modern version of the 1994 legislative pact he made with the American people as he pokes into the middle tier of Republican candidates for 2012.

The entire field is in flux, but Gingrich for the moment has reason to be optimistic. A new Fox News poll showed the race's front-runner, Rick Perry, losing steam and the race's insurgent, Rep. Michele Bachmann, plummeting to the bottom of the pile. With Mitt Romney's numbers holding steady, two candidates made significant gains -- Gingrich and businessman Herman Cain, whose easy-to-grasp tax plan and punchy one-liners have proved effective at recent debates.

Cain rose from 6 percent support in late August to 17 percent in the latest poll; Gingrich rose from 3 percent to 11 percent.

But whereas Cain is peddling a pithy approach to righting the country's economic ship, Gingrich is looking to gain traction by doing what he does best -- outlining big and complex ideas, lots of them, and encouraging supporters to be part of a conservative movement. With him at the helm.

Outlining what he calls a "21st Century Contract With America," Gingrich told Fox News on Thursday the document is "much bigger and much bolder" than what he unveiled with other Republicans before claiming the House majority in 1994.

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"The contract is going to be a very comprehensive document. ... It gives you a sense of the scale of what you should be measuring the president and other candidates against," Gingrich said. "I don't ask people to be for me. ... I ask people to be with me, because this will be an eight-year struggle."

The plan includes a host of across-the-board changes. On taxes, it would allow Americans to choose between paying incomes taxes under the current system or under a lower and simpler flat tax. It would end the capital gains tax and reduce the corporate tax to 12.5 percent. It would let Medicare seniors seek insurance in the private sector and some taxpayers put Social Security contributions in personal accounts.

Like other candidates, he calls for repealing the federal health care overhaul and passing a balanced-budget amendment.

"Part of the solution for America is to get away from a one-size-fits-all bureaucratically defined government dominated by Washington and give the American people the right to have a series of choices," Gingrich told Fox News.

Gingrich's latest showing in the polls, if it holds, marks a significant turnaround from months ago, when he was in the low single digits and half his staff quit en masse -- complaining about his lack of discipline and commitment to the race.

Jeremy Mayer, a public policy professor at George Mason University, said Gingrich remains more electable than other middle-tier candidates like Cain or Texas Rep. Ron Paul. Though Gingrich has struggled in the polls for the past several months, Mayer said he started the race with considerable clout.

However, Mayer said the ex-speaker's burst in the polls may turn out to be a "flutter."

"I think that the Republican unhappiness with their choices is really fueling a second and third and fourth look at Newt Gingrich," he said. "This is a moment for substance ... so Gingrich is going for that substance group within the Republican Party."

But he gave Gingrich a "very small chance" of actually surging to the front and clinching the nomination, calling him "damaged goods" in the eyes of many Republicans.

With the leader board in flux, it seems all the candidates are fighting that much harder.

Bachmann said Sunday that she's being described as the "comeback kid."

"You have candidates go up and you have candidates go down, but now we're in a very good trajectory," she assured supporters.

Perry, after some shaky debate performances, on Wednesday apologized for describing critics of granting in-state college tuition to illegal immigrants as heartless.

Perry's and Romney's campaigns continue to hammer each other. And Romney was out with an op-ed in New Hampshire -- vital territory for the former Massachusetts governor -- outlining his plan for controlling federal spending.

"He has just been focused like a laser beam on all the things he needs to do to get through Iowa and New Hampshire," said Jonathan Collegio, spokesman for conservative fundraising group American Crossroads.