Sen. Cory Booker (D., N.J.) took a shot at Democrats Wednesday calling for the impeachment of President Donald Trump before special counsel Robert Mueller concludes his Russia investigation, saying they "undermine" their positions as Democrats.

MSNBC's "All In" host Chris Hayes asked Booker whether he thought that Trump was a "criminal."

"I'm one of those folks that says let's go where the evidence leads, and right now we have a special counsel that is doing a thorough investigation," Booker said. "Let's not get ahead of our skis. Let's make sure we support the special counsel's investigation. If the president, like he says he has nothing to worry about, he should be backing off on the rhetoric, backing off on the things he's doing to undermine the investigation and let it take its course."

He went on to say it is "politically perilous" how Democrats are getting ahead of the investigation, prompting Hayes to asked Booker whether he is referring to Democrats calling for Trump's impeachment.

"Yeah, look, I think that we undermine our position as Democrats if we are reaching out now for impeachment, which is just going to whip up more of the political divisions, the political debates," Booker said. "I'll take criticism for that, but it's OK. We need to have sober minds, fact-based conclusions, conclusions drawn from evidence as presented."

Booker said if they protect the special counsel and the investigation, they will be able to get all the facts to make the correct decision.

Booker didn't single out any Democrats during his interview, but Democratic Reps. Al Green (D., Texas) and Maxine Waters (D., Calif.) have been vocal about their calls for impeachment.

Waters praised Democrats last month during a MSNBC interview for being "very responsible" in waiting for Mueller's investigation to be over before calling for his impeachment, but she contradicted herself at the end of the interview by calling for Trump's impeachment.

She has been one of Trump's most outspoken critics and has called for his impeachment dozens of times, including a eulogy at a funeral of a civil rights activist last September. Green has filed articles of impeachment twice, but both failed to get past the procedural stage by wide margins.

Another person who has been vocal about impeaching Trump is liberal billionaire Tom Steyer, who has spent tens of millions and sent thousands of impeachment guides to independent and third-party candidates running in the 2018 midterm elections to inform them of what it sees to be Trump's impeachable offenses.

"As a candidate seeking elected office, it is important for you to understand this subject, which is too often misunderstood," the guide read. "Donald Trump is a clear and present danger to our country, and his actions have already superseded the threshold for impeachment as originally conceived by our nation’s Founding Fathers."

Steyer and some of the other Democrats who have called for impeachment have forced House Minority Leader Nancy Pelosi (Calif.) and House Minority Whip Steny Hoyer (Md.) to distance themselves from the impeachment campaign.