Steven Senne, Associated Press
In this Dec. 11, 2014 file photo then-Rhode Island Gov. Lincoln Chafee responds to questions during an interview with The Associated Press, in his office at the Statehouse, in Providence, R.I. Chafee says he has formed an exploratory committee to consider a Democratic presidential campaign, saying in a video that voters want to "assess the character and experience of those offering ideas."

PROVIDENCE, R.I. — From his former deputy, to a top aide, to lawmakers with whom he worked, no one knew Lincoln Chafee had presidential ambitions.

The former Rhode Island governor shocked many, if not all, of his former colleagues Thursday when he announced he had formed an exploratory committee to consider a Democratic presidential campaign.

Democratic state Rep. Mia Ackerman says she can't imagine anyone not being surprised. There was "no buzz, no whispers, nothing," she added.

"When he said he wasn't running again for governor, we all thought he'd enjoy private life," Ackerman said.

Facing poor approval ratings, Chafee decided in 2013 not to seek re-election in what would have been a difficult campaign.

Chafee's Lt. Gov. Elizabeth Roberts and chief of staff, George Zainyeh, also said they had no idea Chafee was considering running in 2016. Zainyeh didn't know of anyone Chafee consulted about his potential candidacy.

Chafee had what one lawmaker described as a "bumpy ride" in the statehouse.

Republican state Rep. Robert Lancia said people were disappointed Chafee didn't do more to improve the state's economy. Rhode Island hasn't rebounded from the recession like other New England states have, and it has struggled for years with one of the highest unemployment rates in the U.S.

Chafee upset some, including Lancia, by refusing to call the evergreen erected in the statehouse every December a Christmas tree, instead referring to it as a "holiday tree" to acknowledge the state's religious diversity, and by allowing a contentious toll to be added to the Sakonnet River Bridge. At the end of his term Chafee shut down the toll.

"I thought he was pretty much done," Lancia said. "But maybe he sees something in the nation and thinks he can make a difference."

Democratic state Rep. John Edwards, the House majority whip, said he was shocked to hear Chafee's news.

"I want to know what his intentions are," Edwards said. "If he couldn't fix Rhode Island, how is he going to fix the country?"

On the other hand, Democratic state Rep. Joseph Shekarchi said, Chafee may "play well" to a national audience, more so than a local one. Chafee could be a "formidable candidate," he added.

"He's more attuned to foreign policy issues than the nitty-gritty of running state government," Shekarchi said.

When he announced his intentions Thursday, the 62-year-old Chafee referenced a 2002 Senate vote by Hillary Rodham Clinton, the presumed front-runner for the nomination, to authorize the Iraq war.

"The voters should have choices and have debates about some of our decisions," Chafee said.

He was appointed to the U.S. Senate after his father, John Chafee, died while serving as a senator in 1999. Chafee was mayor of Warwick at the time.

Chafee won re-election to the Senate the following year as a Republican and cast the party's only vote against the Iraq war. He lost his seat in 2006 to Democrat Sheldon Whitehouse, became an independent in 2007, and narrowly won the race for governor in 2010.

As governor, Chafee legalized gay marriage, started up a state-run health insurance exchange and worked to increase school spending. He joined the Democratic Party in 2013.

State Rep. Joseph McNamara, chairman of the Rhode Island Democratic Party, said Chafee led the state during a difficult time and has strong credentials.

"He's too young to retire," McNamara said. "I was surprised, but I certainly wish him the best."