It has all the early hallmarks of the most curious, quirky, counterintuitive presidential quest by a former member of Congress in a long time. Those who’ve tracked Lincoln Chafee’s strange career would be surprised if it were any other way.

Most politicians time their candidacy announcements for maximum coverage, and pick a setting relevant to their life story or their rationale for running. But the scion of one of New England’s oldest families chose to formalize his intentions during the peak of Wednesday night’s rush hour at George Mason University, a sprawling commuter school in the Northern Virginia suburbs.

During Chafee’s seven years as a senator from Rhode Island, exasperated colleagues and head-scratching staffers openly referred to him as “Missing Linc” because of his manifest disinterest in legislative deal-making and his extraordinarily frequent departures from the party line.

Of course, he was a Republican in those days. And his deviation was most prominent in 2002, when his was the only GOP vote in the Senate against the law permitting the invasion of Iraq.

Chafee has strayed way further since then, becoming an independent in 2007, a year after losing his Senate seat, and then joining the Democratic Party in 2013, near the midpoint of his single term as governor. But his opposition to the war more than a dozen years ago sounds like the principal rationalization for his presidential campaign now. Anyone who backed the war should be disqualified from the White House, he says, because that conflict remains the single biggest reason the world is in such a troubled state and the United States is so poorly positioned to stabilize it.

The intended target of that critique is Hillary Rodham Clinton, who now says she was mistaken to vote for the war authorization while serving as a senator from New York. But while Chafee’s vote set him apart from his former fellow Republicans on the Hill, it doesn’t separate him from the other announced candidates for the 2016 Democratic nomination for president. Bernard Sanders voted “no” as a Vermont senator. Martin O’Malley was mayor of Baltimore back then, but has been a consistent anti-war voice.

Since starting to explore his candidacy this spring, Chafee also has signaled he’ll question some of Clinton’s judgments as secretary of State and the foreign donations to her family’s foundation.

Ideologically, though, it’s not yet clear how Chafee hopes to distinguish himself within his newest political home.

His most prominent enunciation of an agenda came when he was still an independent, when his reward for endorsing President Barack Obama’s re-election was seven prime-time minutes at the 2012 Democratic convention podium. Support for environmental protection, abortion rights, gay rights and deficit reduction (albeit with the help of higher taxes on the rich) made both him and Obama old-fashioned conservatives, he declared, while their shared interest in using federal power to improve education, create jobs, cure disease, promote new energy sources and expand public works meant they were “liberal in the best sense of the word.”

That sounds less like a pitch for the Democratic nomination, however, and more like a recipe for going after the unaffiliated voters central to deciding national elections — and who only sometimes sustained Chafee’s political ambitions in the intimate confines of Rhode Island.

Chafee begins his bid to upset Clinton’s coronation without any of the Sanders grass-roots energy or the O’Malley fundraising potential and organizational ability.

Instead, his most distinguished political feature is his almost timorous affect and his oddball backstory.

His ancestors were among Rhode Island’s earliest settlers, and he was a dorm-mate of Jeb Bush at Phillips Andover before heading to Brown to study classics. But after that, his life started down its defining anti-establishment path. He worked summers in college sweeping up after carpenters and bricklayers at construction sites, and after graduation set off for horseshoeing school at Montana State University. Inspired by the James A. Michener article, “Go Waste, Young Man,” that urged young men to explore the world before settling down, he apprenticed in Kentucky and Florida before spending seven years as a farrier at the harness tracks of northwestern Canada.

“I wanted to see something of life, and I enjoyed working at a trade,” he explained in 1999 for the only profile of a politician ever in “Hoofcare & Lameness: The Journal of Equine Foot Science.”

Returning to Rhode Island in 1983, he worked as a machine shop planner for General Dynamics before changing to the career of his father, John H. Chafee, an icon of liberal Republicanism back when that was a force in the party. He spent five years on the city council in Warwick, the state’s second-biggest city, and was elected mayor in 1992.

He got to the Senate by appointment in 1999, when his father died ahead of his planned retirement after four terms, and he was elected in his own right a year later. During every year as a senator, he went against the partisan grain more often than any other Republican, and in four years he opposed President George W. Bush more often than anyone else in the Senate GOP. (He announced in 2004 that he would not vote for Bush’s re-election.) But Chafee’s apostasy went unpunished: He made it clear that excessive pressure from the White House or Senate leaders would lead him to bolt the party, and they essentially gave him license to oppose them at will if that would assure his survival in his lopsidedly Democratic state.

It didn’t, and months after handily losing in 2006 to Democrat Sheldon Whitehouse, Chafee declared himself an independent. That positioning helped him stage a comeback in 2010, winning the governorship with 36 percent of the vote against the major party candidates. But, just months after finishing his political journey and joining the Democrats, shrinking poll numbers and the threat of a primary challenge within his new party prompted him to abandon plans to seek a second term.

Now, this 62-year-old politician with three different party affiliations on his record, and two unhappy endings in statewide office under his belt, thinks he can unify the Democratic Party and win election as the most powerful person on Earth. His rationale is as much of a cliché as his résumé is not: “America loves an underdog.”

Related:

Chafee Fact File

Sanders Asks Democrats to Pick Proud Non-Democrat

Vote Studies Track Presidential Hopefuls in Real Time

Rhode Island Bottleneck Could Tighten by 2022

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