Rhode Island Governor Lincoln Chafee (R) gestures after signing the the Marriage Equality Act into law and handing it to Speaker Gordon Fox (L) at the State House in Providence, Rhode Island, May 2, 2013. Rhode Island became the 10th U.S. state to extend marriage rights to same-sex couples. REUTERS/Jessica Rinaldi (UNITED STATES - Tags: POLITICS SOCIETY)
Rhode Island Gov. Lincoln Chafee, right, after signing the the Marriage Equality Act at the State House in Providence, R.I., on May 2. (Jessica Rinaldi/Reuters)

Rhode Island Gov. Lincoln Chafee (I) intends to run for reelection as a Democrat, according to two people familiar with his decision, a move that suggests that the first-term governor does not see a path to reelection as an independent.

Chafee, a former Republican senator, won the governorship in 2010 in a competitive three-way race. His prospects for a second term have looked dim, as polling shows his numbers are downright bad. Chafee's made no secret about the fact that he has been considering switching to the Democratic Party. His decision signals that he believes his best chance for survival is competing in what is expected to be a competitive Democratic primary.

Chafee is expected to announce his decision shortly, possibly as soon as this week, the people familiar with his decision say.

The Democratic Governors Association has said it will not endorse a candidate in the primary, opting instead to simply support the eventual nominee, whomever it ends up being. Treasurer Gina Raimondo and Providence Mayor Angel Taveras are expected to enter the Democratic race, and each looks like a stronger option for the general election than Chafee.

When asked about the governor's future plans, Chafee spokeswoman Christine Hunsinger would not confirm or deny that Chafee will become a Democrat. "I just don't have anything for you on it," she said.

Chafee's decision is good for Democrats for a couple of reasons. One, it takes off the table the threat of a vote split between the Democratic nominee and the governor, something that could open the door for the Republican to win, even in a Democratic-leaning state. If Chafee loses the Democratic nomination — and it is hard, at least at this point, to see him winning — then he is out of the picture altogether. Of course, if he wins, Democrats would have to back a pol with a struggling image in the eyes of Republicans.

Without saying he supports Chafee in the Democratic primary, Obama welcomed his former Senate colleague and key political ally to the party with open arms on Wednesday.

“I’m delighted to hear that Governor Chafee is joining the Democratic Party,” Obama said in a statement distributed by the Democratic National Committee. “For nearly 30 years, Linc Chafee has served his beloved Rhode Island as an independent thinker and leader who’s unafraid to reach across party lines to get things done. I enjoyed working with Linc when he was a Republican in the United States Senate, and I look forward to continuing that collaboration on the issues that matter not just to the Democratic Party, but to every American.”

DGA Chairman Peter Shumlin of Vermont welcomed Chafee, but said the DGA plans to support whichever candidate wins the Democratic nomination.

"We are excited to welcome Governor Chafee to the ranks of Democratic governors and look forward to enthusiastically supporting whoever emerges as the Democratic nominee in Rhode Island," Shumlin said in a statement.

Chris Cillizza contributed to this report.

Updated at 4:26 p.m. 

Sean Sullivan has covered national politics for The Washington Post since 2012.