Rhode Island Gov. Lincoln Chafee, who served eight years in the Senate as a Republican before declaring himself an independent, is changing his party affiliation again and becoming a Democrat. Chafee has a history of clashing with Republicans — he was ranked as the most liberal Republican in the Senate during his years on Capitol Hill, and was one of the few to vote against the Iraq war in 2003. He made the split clean in 2008, when he endorsed Barack Obama for president and launched his successful bid to become the first independent governor elected in Rhode Island since the 18th century.

So why is Chafee switching again? One theory is that he's playing politics. Chafee has been dogged by low approval ratings, and he's up for re-election next year. Sean Sullivan at The Washington Post points out that if Chafee ran as an independent, he would have to beat two well-funded opponents — a Republican and a Democrat — instead of just one. "Chafee's wagering that he stands a better chance of winning what is now expected to be a three-way Democratic primary — with two strong up-and-coming candidates — than he would have in the general election scenario described above."

But even in the Democratic primary, Chafee faces an uphill climb. Treasurer Gina Raimondo and Providence Mayor Angel Taveras have been expected to run for some time, and there's no indication they'll step aside for the incumbent...

We'll find out in the coming months whether his decision will be an example of deft dodge of near-certain defeat or whether his name will be the added to the ignominious list of politically motivated party-switchers. [Washington Post]

Even if Chafee winds up losing, he's probably ensuring that he'll get a consolation prize in 2014. As Rick Moran puts it at PJ Tattler, Chafee's switch spells near-certain doom for his old foils in the GOP and "virtually assures a Democratic win in the governor's race next year." In a three-way race, the liberal and moderate vote would have been split between Chafee and a Democrat, Moran says, but now all of that support will go to the candidate left standing after the Democratic primary:

The Rhode Island Republican party has no statewide office holders, no congressmen, and few proven vote-getters. Cranston Mayor Alan Fung, the first Asian-American mayor in Rhode Island, has expressed interest in running for the GOP nomination, but with Chafee's decision to run as a Democrat, the odds of a GOP victory have lessened greatly and Fung may choose to sit this one out. [PJ Tattler]

The Chafee camp, however, says there's a much simpler explanation — the governor is just moving where he truly belongs. "What you're seeing in him affiliating as a Democrat is a recognition that there's strength in numbers," and that he shares the "agenda and the policy beliefs" of the president and the Democratic Party, Chafee spokeswoman Christine Hunsinger said. Obama welcomed Chafee to his party, saying he looked forward to collaborating with his former Senate colleague "on the issues that matter not just to the Democratic Party, but to every American."

Many outside observers buy the argument that Chafee's just taking the last step down a long road leading away from the GOP and toward the Dems, at least to a point. Here's James Joyner at Outside the Beltway:

This move is hardly surprising. Chafee has been at odds with the GOP for more than a decade and not only endorsed Obama in 2008 but [also] served as his state chairman. He spoke at the 2012 Democratic convention, too. Still, it's yet another in a long series of signs that the northeastern wing of the GOP, long known as "Rockefeller Republicans," is extinct. [Outside the Beltway]

In that case, Chafee's move is but a symbol of a larger trend — unless it is just politics.