WASHINGTON (AP) - Former House Speaker Newt Gingrich's stunning surge toward the top of the Republican presidential field has unnerved some Republicans in Congress who remember too well the tumult of nearly two decades ago.
"I'd rather have steady," said Rep. Steve LaTourette of Ohio, who just this week made it known that he was backing former Massachusetts Gov. Mitt Romney instead of the resurgent Gingrich, the man who led the 1994 "revolution" in which LaTourette was first elected.
Personally, LaTourette said, he has a "hangover" from the days of Gingrich's speakership, when "everything always seemed to be on fire."
In interviews this week, more than a dozen Republican members of the House and Senate wouldn't say - when given repeated chances - that they are confident that Gingrich has the discipline and stamina to outlast Romney and, down the road, face President Barack Obama in a grueling general election.
Gingrich has had trouble marshaling support from Congress' mass of political insiders. The 1994 "revolutionaries" who turned Democrats out of power for the first time in 40 years as well as more senior lawmakers waver on the question of whether Gingrich would be good for the GOP and the country given his rocky past.
Sen. Pat Roberts of Kansas, who credited Gingrich with helping push through a transformative farm bill, is among those unsure whether Gingrich-as-nominee would be helpful.
"It depends on what he does," said Roberts, who has not committed to a candidate for the party's nomination.
For his part, Gingrich told CNN late Wednesday: "I wish everybody had loved me. But I'd rather be effective representing the American people than be popular inside Washington."
"My job was to drive through change on a scale that Washington wasn't comfortable with, and you know, if you're a genuine outsider, forcing change, you're going to leave some bruised feelings," he added. "I don't apologize for that. I think I probably learned some more. I think I'll probably be more effective this time."
Gingrich's Capitol Hill days were volatile to say the least.
He was at the helm during two government shutdowns. He had a snit over a back-seat assignment on Air Force One and displayed a management style that his allies said shifted wildly and eroded morale among his backers.
There also was the book deal that led to a $300,000 fine from the House ethics committee and enough chaos to inspire his own lieutenants to plot Gingrich's overthrow. And who could forget Gingrich's illicit affair with a House aide - now his wife, Callista - while advocating for President Bill Clinton's impeachment after a sexual impropriety of his own?
Now a presidential candidate, Gingrich, at 68, claims he's matured. But his unpredictability remains a concern to some, and he's clearly aware of the political jitters his campaign's newfound viability gives to those who know him best.
He reached out last week to Sen. Lindsey Graham, the South Carolinian who won a House seat in the 1994 election and became disillusioned enough four years later to huddle with Gingrich's leadership team and consider mutiny.
Gingrich called Graham and the two had an hourlong conversation.
"He certainly doesn't hold grudges, because the coup (meeting) was held in my office," said Graham, who has not endorsed anyone in his state's important early primary. He came away from the talk feeling better about the relationship, and the candidate.
"I think he has learned from those experiences, and the conversation I had with him was reassuring. The guy I'm talking to was a different guy than 1997," Graham said. "He mentioned that he thinks he's more settled. And I said, "Good."'
There's more to Gingrich's reassurance campaign.
On Wednesday, he summoned conservative leaders to a private, two-hour meeting at which he took blunt questions about his "discipline and structure," the $300,000 ethics fine, and a hard-to-forget television ad in which he sat shoulder to shoulder with Rep. Nancy Pelosi, herself a former House speaker as well as a liberal stalwart.
Tea Party Express Chairwoman Amy Kremer, who attended the event, said Gingrich promised to continue to be honest about mistakes he's made in his personal life and sought to alleviate concerns in other areas.
It's a message Gingrich has been delivering repeatedly since launching his presidential campaign last spring. Only now, people are paying attention, given that polls show him leading the GOP field in Iowa and elsewhere.
On Capitol Hill, perhaps no one knows Gingrich better than House Speaker John Boehner, who lost his leadership role after the coup attempt.
But Boehner won't weigh in on the race, saying Wednesday, "Newt has been a longtime friend, but my focus is on what American people sent us here to do, which is focus on jobs."
Former Vice President Dan Quayle, who has endorsed Mitt Romney, answered "yes" when asked on NBC's "Today" show Thursday if Gingrich could beat Obama.
Scores of congressional Republicans are staying out of the contest, including some whose work with and respect for Gingrich go back decades. Among those, the hesitation comes from uncertainty, they said. Many offered respectful words but refused to say whether the former speaker would make an effective opponent to Obama or, perhaps, an effective president.
"Well, that's not up to me to judge," said Sen. Orrin Hatch of Utah, who has endorsed Romney. "All I can say is Newt is a wonderful idea man. He's not as good about implementing ideas. He moves from issue to issue really fast. And in some ways that's good, but you got to be able to implement" ideas.
Sen. John McCain of Arizona, the party's 2008 nominee against Obama, issued a classic non-endorsement.
Would he be pleased to see Gingrich win the nomination?
"Look, I respect the process," McCain said. "I think it (would be) quite an achievement."
Gingrich is not without allies and admirers on Capitol Hill.
At least six members of Congress have endorsed him, and Rep. Jack Kingston of Georgia is trying to set up a meet-and-greet with uncommitted members next week.
And Sen. Rob Portman of Ohio, who was a rookie House member when the GOP won Congress in 1994, said he sees Gingrich as a throwback to the old days of bipartisan lawmaking for which so many lawmakers and Americans say they yearn. Behind closed doors, Portman recalled, Gingrich is an apt negotiator. And he does focus, Portman said.
"He does have a history of managing through a tough issue and coming up with a result," Portman, who intends to stay neutral in the nominating fight, said Wednesday. He was careful to mention that he thinks Romney would do just as well at governing.
Associated Press writer Steve Peoples in Concord, N.H., contributed to this report.