Jae C. Hong, Associated Press
Former House Speaker Newt Gingrich, speaking recently, won't be running in '08. Pledges in the millions came in the first week amid the rumors.

CARROLLTON, Ga. — Former U.S. House Speaker Newt Gingrich on Saturday decided against running for president in 2008, less than a day after the Republican indicated publicly that he would spend the next month exploring the viability of a White House bid.

Gingrich said the last-minute change of heart, which came as aides readied the NewtNow.org Web site and prepared to file campaign papers, was the result of legal advice that running for president would require stepping down as chairman of his nonprofit organization, American Solutions.

That group is the latest vehicle for Gingrich's musings about politics and policy, and opened its first annual "ideas summit" Saturday at a Georgia college an hour west of Atlanta and with webcasts on the Internet.

"American Solutions is in the early stages, I think, of becoming a genuine national citizens movement," Gingrich told reporters. "To walk out of it just as it's getting launched struck me as absolutely irresponsible."

Gingrich has spent the better part of a year teasing the media and his supporters with the idea that he might run for president. He has condemned the political process that requires candidates to start campaigning years ahead of the election and to raise tens of millions of dollars.

At times, his criticism of the American electoral process made it sound unlikely that he would run. But more recently, he said he would run if he received $30 million in pledges toward a presidential campaign.

Aides had scheduled a news conference for Monday morning in which Gingrich was set to announce the formation of an exploratory committee. Randy Evans, Gingrich's lawyer, said they had prepared the papers, opened a bank account and severed Gingrich's ties as a consultant for Fox News.

Evans said that since word leaked out a week ago, Gingrich had received pledges "in the millions, I'll make no bones about it."

But at about 11 a.m. Saturday, Gingrich said, Evans told the former lawmaker that the McCain-Feingold campaign finance laws would make it a criminal offense for Gingrich to form the presidential exploratory committee while continuing to run the American Solutions organization.

"The McCain-Feingold act is a very anti-middle-class act," Gingrich said. "There are such severe penalties. I would have to have stepped down and resigned. ... That basically ended the conversation."

Gingrich has been a fiery figure since he burst onto the national stage in 1994 with the "Contract With America," a list of 10 pledges that helped Republicans seize control of the House and launched Gingrich into the speaker's office.

From that perch, he became a larger-than-life figure, espousing conservative principles and battling with then-President Bill Clinton. Gingrich helped lead the campaign to impeach Clinton but resigned himself in 1998 after midterm elections that disappointed the GOP.

In recent years, however, Gingrich has tried to rehabilitate his reputation. He has become a conservative gadfly, writing novels and policy prescriptions, sometimes to Republicans' chagrin.

He has said the American Solutions organization is intended to be a bipartisan effort aimed at finding "real solutions" to the nation's problems. The summit featured sessions from conservatives such as former representative Dick Armey, R-Texas, and former Colorado Democratic governor Roy Romer.

A video played at the beginning of the summit said: "Red Country? Blue Country? Americans are tired of Red vs. Blue. We need a Red, White and Blue country."

Whether that sentiment would have translated into votes in a possible presidential campaign is anyone's guess. Several of the 100 or so summit attendees said they admire Gingrich's creativity but are not sure he would be a good president.

Jim Bourland, 50, a general contractor from Columbus, Miss., drove 3 1/2 hours to spend the day in western Georgia with Gingrich. But he arrived wearing a T-shirt proclaiming former Massachusetts governor Mitt Romney "Mr. President."

"We're looking for a good vice president," Bourland explained.