In late February, when long-retired Nebraska senator Bob Kerrey revealed that after much agonizing (having decided the opposite a few weeks earlier), he was going to re-enter the game and run for the open Senate seat in his native state, Republicans were quick to pounce.

“[T]hree weeks after New York City resident Bob Kerrey told Nebraskans that he was putting his family first and staying in his beloved Greenwich Village home, he has had a sudden change of heart,” began a sarcastic communiqué from the National Republican Senatorial Committee.

“That part’s true,” Kerrey tells me matter-of-factly. “Although it’s called the West Village. Sorry to give them a geography lesson.”

The decision by the 67-year-old Kerrey, who has a school-age son with his screenwriter-wife, Sarah Paley (and two grown children from a previous marriage), was greeted with jubilation and relief by the White House and the Senate Democratic caucus, which see him as the party’s best hope to hold the precarious seat about to be vacated by centrist Democrat Ben Nelson and give the Dems a chance of retaining a wafer-thin majority.

It was, naturally enough, a tough call for Kerrey to uproot his family from Manhattan, where he spent the past decade as president of the New School, and leap into a down-and-dirty political battle. Already the state GOP is calling Kerrey a carpetbagger and pursuing a legal challenge to his residency and voting status, notwithstanding a grudging ruling by Nebraska’s secretary of state, a Republican, that Kerrey is legit.

“We have a very good life in New York City, and life on a political campaign is considerably worse,” Kerrey says by cellphone as he rides between campaign events in Lincoln and Omaha. “I’ve neither asked for nor expect sympathy for that. It is a big change. But it’s not the worst transition to move from New York to Nebraska.”

And is his wife committed to his surprising career choice?

“She’s driving the car!”

Kerrey, a congenitally restless man whose tenure at the New School was marred by controversy and conflict (with students, faculty members and various unions, amid persistent budgetary problems), has flirted before with a return to politics. He thought about running for mayor of New York City in 2005 and then for the Senate when Nebraska Republican Chuck Hagel announced his retirement in 2007. Three years later he almost accepted the presidency of the Motion Picture Association of America—a high-dollar job that ultimately went to former Connecticut senator Chris Dodd—but couldn’t agree on terms. So why, in the end, did Kerrey jump back in the fray?

“I value public service and I’m relatively good at organizing political causes,” he explains, “so the experience taught me that I enjoyed it. I learned a lot being out, and I think it helps being out awhile. What really called me back is what I would say are three or four significant problems”—such as mushrooming federal debt and trillion-dollar deficits, unfunded entitlements, exploding health-care costs, and the deteriorating quality of education and the environment—“which, if left unaddressed, the country’s going to be much, much weaker as a consequence. It’s the belief that public service is worthwhile, and I felt like I was going to regret at least not making the effort.”

Kerrey, who was a member of the Senate Intelligence Committee and, after leaving the Senate, served on the 9/11 Commission and the deficit-hawkish Concord Coalition, is well-versed in the nuances of domestic and foreign policy. He speaks with equal fluency about health care, tax policy, Afghanistan, and Iran. Obama is following the right course in both hotspots, he believes. Concerning the recent killing of 16 unarmed Afghan civilians by—allegedly—a U.S. Army staff sergeant, Kerrey speaks with special authority: He’s a Vietnam-era Navy Seal whose combat heroism (during which he lost part of a leg) earned him the Medal of Honor.

“It looks to me like it’s a consequence of severe stress and multiple tours,” he says of imprisoned Staff Sgt. Robert Bales. “It’s likely that the young man in question is mentally ill, from what I’ve read thus far…I don’t think our military strategy in Afghanistan ought to be dictated by this event.”

Kerrey can also deliver a learned disquisition on the ins and outs of Nebraska’s roaring agriculture sector—which accounts for the state’s enviable unemployment rate of around 4 percent. Even so, Kerrey says Nebraskans are anxious about the economy and deeply concerned about the national debt. In the event he wins and is returned to the Senate, “the top of the agenda is immediately to become part of the effort to get our fiscal house in order,” he says. “Get the debts under control, especially the entitlements, and forge common cause with Republicans as quickly as possible. I don’t know how it’s going to be, because it’s not an easy thing to break with your caucus.” Kerrey favors raising taxes on individuals earning over $250,000, coupled with the continuation of a payroll tax cut. “This problem is not going to go away. It’s got to get solved, and trying to apply a standard of fairness and justice is the correct thing to do.”

Kerrey acknowledges that success is elusive; Congress has never been more ideological. “The center has shrunk,” he muses.

But getting himself back to Washington won’t be easy either. Nebraska is the reddest of red states, where John McCain beat Barack Obama by 15 points in 2008, and the president remains deeply unpopular. Kerrey refuses to distance himself from the nation’s top Democrat. He hasn’t always agreed with the president, especially Obama’s reluctance to embrace the Simpson-Bowles deficit reduction plan, but Kerrey believes he has done a good job on the whole, and says he’d welcome Obama to Nebraska to campaign and, even better, raise money for him. Vice President Biden, a colleague from the Senate, was among the old friends he consulted about making the race.

Yet he’s happy to take potshots at the White House staff, especially David Plouffe, the razor-tongued, brass-knuckled political and communications czar. “He used to be a really lovely young man,” says Kerrey, who hasn’t spoken with Plouffe since leaving the Senate in January 2001. “Now it looks like he could eat an apple through a tennis racquet." (Plouffe had no comment.)

Kerrey has a blunt-spoken way with words—most famously in an expletive-punctuated phone call with President Clinton over his resistance to casting a crucial vote in favor of Clinton’s 1993 budget. (Not enough deficit reduction, Kerrey complained.) After slamming down the receiver on his 1992 presidential primary opponent (Kerrey was no match for the Clinton juggernaut), he snuck out of his Senate office to catch a matinee of the Tina Turner biopic, What’s Love Got To With It?

“The movie didn’t influence my decision, by the way,” recalls Kerrey, who “was trying to get away from the press that was hounding me outside my door asking how I was going to vote. My mood was affected, but not my vote.” In due course he relented and voted for the deal.

Kerrey—who ran successful restaurant and health-club chains before serving as both governor and a two-term senator—is a rare maverick Democrat, sometimes liberal, sometimes not, who managed to command the votes and respect of a conservative electorate. There’s even a footbridge named after him in Omaha.

But he’s been gone a very long time, A recent Rasmussen poll had Kerrey trailing badly against any of his three likely GOP opponents, and also suffering upside-down popularity ratings.

“They significantly oversampled Republicans to get that conclusion,” Kerrey argues. “But, yes, I’m an underdog.”

He figures he will need to collect from $8 to $10 million to see him through the general election, “and that doesn’t count super-PACs,” he adds. He says Karl Rove’s American Crossroads, as well as the notorious Koch brothers, “have been on”—with anti-Kerrey spots—“almost continuously since there was a possibility I would run. They’ve spent several hundred thousand dollars already…I expect there will be some super-PAC activity on my side as well.”

But it won’t be funded by his friend Warren Buffett, the Oracle of Omaha, nor by Warren’s daughter Susie, who took Kerrey to a high school basketball game on the night he announced. “Both are pretty strong for campaign finance reform,” Kerrey says. “They haven’t told me that [they won’t donate to a pro-Kerrey super-PAC], but I’m pretty certain that’s their position.”

Kerrey recently signed pollster Harrison Hickman—whom he suspended from his 1992 presidential campaign, angrily calling him “Harrison Hitman” after Hickman admitted to anonymously faxing damaging information about Clinton’s draft record to members of the press. Kerrey, like every politician, is an avid consumer of polling data. And, like every politician, he wants to be loved. But he claims he won’t pander.

“I’m going to tell the truth as I see it,” he vows. “Now, about the only people who are telling the truth all the time are probably the ones on the street corner saying the world’s going to come to an end. So I don’t want to be foolish about it. But on the big things, I’m not going to trim in order to win public opinion. Because I really don’t want to serve in the Senate if I arrive there without permission to do the things I think need to be done.”