NEWTON, Mass. -- In the Bay State, Republican Senator Scott Brown continues to stay afloat in an overwhelming sea of blue.

Boasting solid job approval ratings, a robust campaign war chest, and a New York Times best-selling autobiography -- all while occupying the Senate seat formerly held by Edward M. Kennedy, no less -- Brown is well positioned to make a strong case that his 2010 upset victory was no fluke.

But one aspect of Sen. Brown's tenure is a fluke: Because he ran for Ted Kennedy's unexpired term, he has to run for re-election next year instead of getting a six-year senatorial grace period. And more than a year removed from their rude awakening here in Massachusetts, Democrats are determined to oust the junior senator and recapture a seat they believe should have never been lost.

"It's a myth that he's politically invincible," Democratic Senatorial Campaign Committee spokesman Matt Canter said of Brown. "He has a glass jaw, but no one's really taken a good swing at it yet."

Though a flurry of Democratic candidates are expected to line up to deliver their jabs to Brown in the coming months, one name in particular has recently garnered local attention: Mayor Setti Warren of Newton. Only 15 months into his first term serving this affluent suburb of Boston, Warren had already been the target of much speculation surrounding a possible Senate run even before Gov. Deval Patrick pushed him into the public eye when he told National Journal on Feb. 28 that Warren was "in, for sure."

Warren, 40, is a fresh face among a field of potential candidates that includes veteran Bay State Democrats ranging from Rep. Michael Capuano to City Year co-founder Alan Khazei.

While this is Warren's first time holding elected office, his resume features political experience at both the local and national levels: special assistant in the White House Office of Cabinet Affairs during the Clinton administration, New England director of the Federal Emergency Management Agency, senior adviser to Sen. John Kerry.

But above all else, some believe he might just have the charm and charisma to compete with Brown’s pickup truck and barn jacket on the campaign trail. 

Warren has not said definitively whether he'll challenge Brown, although he is increasingly sounding like a candidate. "My consideration is really based on the final analysis of whether I'd do a better job for Massachusetts," Warren said in an interview with RealClearPolitics. "Many of us believed that Scott Brown was going to be an independent voice here in the state, but he hasn't been."

Truth be told, Brown has broken ranks with the Republican leadership in the Senate on any number of momentous issues: He voted to repeal "Don't Ask, Don't Tell," to ratify the START treaty, and he supported financial regulatory reform.

In fact, these votes have provoked the ire of Tea Party activists whose support and financial backing helped propel Brown from relative obscurity to the United States Senate in an upset that heralded the arrival of a potent new conservative force within the GOP, as well as independents' disaffection from Democrats in the Age of Obama. Now, however, disgruntled Tea Party leaders have recently been threatening not just to withhold support for their former darling's re-election bid, but also to mount their own primary challenge with a purer conservative candidate.

In any event, the Tea Party’s disapproval will likely be viewed with much favor in one of the bluest of the blue states. Not to mention, Brown’s grassroots movement in 2010 has since given way to a formidable juggernaut equipped with millions of dollars in funding, statewide organization, and a candidate at the helm who has become both a local and national icon.

To be sure -- with polls showing that 73 percent of Massachusetts voters are unaware of who Setti Warren is -- it's the young mayor who will have to emulate his potential opponent's 2010 ascent if he wants to best him in 2012, several experts say.

"He needs to look in the mirror and ask, can I do what Scott Brown did?" said Democratic strategist Mary Anne Marsh. "And then he'd need to turn around and beat him in a six-week race after what will likely be a competitive, bloody, and expensive primary."

Even if Warren were to survive that Democratic primary, he will have to contend with a potential stature gap with Brown. Although little known nationally when he garnered Kennedy's seat, Brown was somewhat familiar to voters in Massachusetts where he had extensive tenure in town government along with six terms in the state legislature.

Warren is also seen by many as a member of the state's liberal elite, a native son of well-to-do Newton and a former transplant in Washington with close ties to establishment figures like Kerry and Patrick. Brown, on the other hand, played pickup truck politics in 2010 to become what some viewed as a working-class hero -- an average Joe who drops his R's and drives a GMC Canyon.

"In a way, I feel sorry for his opponent because I know how strongly Scott will work for his re-election," said Brown's political adviser Eric Fehrnstrom, who refused to speculate on potential Democratic candidates. "He's the only political figure I know who marches in parades in off-election years and likes it."

Perhaps, but Warren's résumé may trump the pageantry of Memorial Day parades. While Brown earned points for his service in the Massachusetts National Guard, Warren, who enlisted in the U.S. Naval Reserves after September 11, recently completed a tour of duty in Iraq.

"My family has a tradition of service in the military," said Warren, whose father and grandfather served in the Korean War and World War II, respectively. "Part of my commitment to public service, to the country, is to continue that tradition."

And in a state once marred by racial turmoil -- where the image of a young black lawyer being stabbed with an American flag in front of Boston City Hall cast a long shadow over Massachusetts politics -- voters here have largely come to embrace African-American politicians such as Warren. Patrick became the state's first black governor in 2006, and two years later Obama carried Massachusetts in the presidential election with 62 percent of the vote.

For Warren, the son of parents who marched for civil rights in the South, the opportunity to become the U.S. Senate's only African-American member would be significant. "My parents put their lives on the line to desegregate lunch counters and movie theaters," he told RCP. "They really instilled in me the value of commitment to community, commitment to city and country."

Although he's not saying for sure, all signs point to Warren running. The mayor has been traveling outside the friendly confines of Newton lately, visiting cities across Massachusetts in apparent attempts to improve his statewide recognition. Most recently he appeared at the president's speech at a Dorchester public school, where he said the two discussed the upcoming campaign. Just a week later, after he met with DSCC Executive Director Guy Cecil, it was reported that Warren's political director Deborah Shah sent out an e-mail seeking young and experienced staffers for his potential Senate campaign by the end of April.

And, of course, it was his friend the governor who outed him in the first place. Mary Anne Marsh believes that Patrick, who will likely be a top surrogate for Obama in his 2012 re-election bid, did this to shift the spotlight away from himself and quell any speculation that he might run for Senate.

"While a lot of these names had been rumored already, for Governor Patrick to publicly mention them meant people would take it as fact," Marsh said. "It certainly helped take pressure off Governor Patrick because now the focus is on potential contenders like Setti Warren."

Now, with the eyes of the local media upon him, Warren reflects on the 2010 special election knowing full well that Democrats have a difficult race before them, despite their nearly 8-1 statewide advantage in party registration.

"I think we were all surprised that we lost," he said. "But you learn the lessons of the past, and right now I'm looking ahead to the future."