PROVIDENCE, R.I. — Former U.S. Sen. Lincoln Chafee said Thursday he will take more time, "perhaps weeks," to mull a bid to regain his Senate seat, adding that he has changed his mind and would now support legislation protecting special counsel Robert Mueller.

Chafee, also a former Rhode Island governor, surprised many last week when he said he would likely challenge U.S. Sen. Sheldon Whitehouse in a Democratic primary. He told The Associated Press he would likely decide whether to run this week.

But on Thursday he told the AP he would seek more feedback and possibly commission a poll to see if primary voters are concerned about the issues he has raised.

Chafee served as a Republican senator for seven years before Whitehouse defeated him in 2006. He then served as governor as an independent from 2011 to 2015, when he unsuccessfully ran for the Democratic nomination for president.

Before announcing his renewed interest in the Senate, Chafee had been considering another run for governor. He said Thursday he's no longer considering that option.

Chafee also changed his mind about whether he would vote to safeguard the special counsel, whose Russia investigation has divided Republicans. He said last week that he wouldn't support legislation in the Senate to do that but said Thursday he would have "voted with the Democrats."

Whitehouse was among a bipartisan group of senators — 10 Democrats and 4 Republicans — in the Senate Judiciary Committee that passed the measure , 14-7, on April 26. Republican Senate Majority Leader Mitch McConnell said the bill is unnecessary and that he won't let it reach the full Senate floor.

Chafee said he "wasn't tuned in" to the vote when he made the comment last week but remains concerned about the amount of attention the Russia probe has commanded among Democrats.

"From a partisan Democratic viewpoint, I am concerned that we might be playing into the Republicans' hands in that many of them would prefer (Vice President Mike) Pence as the top of their ticket" in 2020, Chafee said. He said establishment Republicans "may quietly not object" if Trump is impeached.

Chafee said he disagrees with everything Trump stands for, but the country has to let him "sink or swim."

"And we're spending an awful amount of time on this investigation," he said.

At an event Thursday, Whitehouse pushed back against the criticism, saying it's surprising to hear anyone outside Trump's orbit question their efforts.

Whitehouse, a former federal prosecutor, said the Mueller probe is "the most principled, thorough and determined investigation that I have seen in my career."

Chafee said if he were in the Senate he would focus instead on reforming what he called a "broken" Democratic National Committee.