PROVIDENCE, R.I. (WPRI) – Former Rhode Island Gov. Lincoln Chafee says he is “very likely” to enter the Democratic primary against the man who defeated him for the same seat 12 years ago, Sheldon Whitehouse, Eyewitness News has confirmed.

Chafee, 65, said Whitehouse’s lukewarm job approval rating in last month’s WPRI 12/Roger Williams University poll has influenced him, along with the urging of some Bernie Sanders supporters, who he said first approached him a few months ago.

“Their motivation was that Sheldon Whitehouse had voted for Hillary Clinton at the Democratic convention even though almost every city and town in Rhode Island had supported Senator Sanders in our Democratic primary for president,” Chafee told Eyewitness News. He also cited Whitehouse’s recent vote against a Sanders-sponsored resolution to pull U.S. troops out of Yemen.

As for the WPRI 12/RWU poll, Chafee said the survey results “jumped off the page, and Senator Whitehouse just doesn’t have solid support according to that poll here in Rhode Island.” The survey showed 46% of voters say Whitehouse is doing an excellent or good job, 22% say he is doing a fair job and 27% say he is doing a poor job.

Whitehouse is already set to face two Republican challengers, state Rep. Bobby Nardolillo and former R.I. Supreme Court Justice Robert Flanders. He has amassed more than $3 million to fund his re-election bid, far more than the two GOP candidates.

“The primary is really the election in Rhode Island,” Chafee said, adding: “I learned the hard way losing in 2006 what an anchor that ‘R’ was next to my name.”

It’s another surprise announcement by Chafee, who for much of the last year has indicated he was considering a comeback bid for governor and later revealed he would do so by entering the Democratic primary against current Gov. Gina Raimondo.

But Chafee said Wednesday he has no interest now in running for governor – or Warwick mayor. The latter job is expected to open up with the looming departure of Scott Avedisian, a Chafee protege.

Whitehouse aides did not appear to see Chafee’s move coming. Asked about his formal rival’s decision, Whitehouse issued a statement that made no mention of Chafee.

“I look forward to spending the months ahead talking with the people of Rhode Island about how I’m fighting every day in the Senate to grow the middle class, protect health care, and leave our planet a better place for the next generation,” he said. “I welcome any and all Rhode Islanders to take part in that conversation.”

Chafee won election to the U.S. Senate as a Republican in 2000 after succeeding his late father, John Chafee, but lost to Whitehouse six years later. He went on to win the governor’s office as an independent in 2010, only to join the Democratic Party in 2013. He declined to seek re-election in 2014, then made an unsuccessful bid for the Democratic presidential nomination in 2015.

Chafee’s family is independently wealthy, which would give him the resources to mount a competitive campaign if he chose to spend the money, although he ran his presidential bid on a shoestring budget.

Nardolillo, one of the Republicans running for Senate, welcomed Chafee’s announcement. “As I look around at every other candidate anywhere in this race, I see me and a growing group of elitists who are out of touch with the people they seek to represent,” he said.