Some moderate Democrats are still undecided on impeachment. They explain why.

With a House floor vote on impeachment rapidly approaching, many moderate House Democrats said on Thursday they're still reviewing the charges drawn up against President Donald Trump, and will use the weekend to decide how to cast the most consequential vote they've taken in Congress.

House Speaker Nancy Pelosi, calling the vote a deeply personal decision for members, said Democrats have no plans to whip members to vote for the articles.

They can only afford to lose 16-17 of the 233 Democrats to be able to pass the charges and formally impeach Trump.

Despite Republicans repeatedly warning Democrats in Trump districts they risk getting beaten in 2020, Democratic aides and leaders say privately they aren't worried about the vote, and expect just a handful of defections.

Still, some Democrats aren't showing their cards.

"I have made my way almost through the entire thing. I will read the rebuttal piece from the minority side. I've gone back and forth and looked at the House rules, I'm looking at the Nixon documents, the Clinton documents just to do what I was trained to do and make an objective decision based on what I think is right," Rep. Elisa Slotkin, D-Mich., a former CIA officer and Pentagon official, told ABC News Live Senior Washington Reporter Devin Dwyer.

Rep. Max Rose, a New York Democrat and Army veteran who represents deep-red Staten Island and slices of Brooklyn in Congress, said the vote will come down to "showing integrity, trying to abide by and uphold my oath to the Constitution."

"I'm not operating on anyone's timeline but my own," he told Dwyer when asked about making up his mind.

Rep. Elaine Luria of Virginia, a U.S. Navy veteran who co-wrote a Washington Post op-ed with a group of House Democratic freshmen with national security experience in September that helped push the caucus towards impeachment over the Ukraine scandal, said she plans to vote for both articles.

"I've always said it was not a political decision it was about what was wrong and what was right," Luria, whose Virginia Beach district was carried by Trump in 2016, told reporters.

"If I don't get reelected in 2020 because of it I'll know that I did the right thing and was on the right side of history, and I'll be able to look at myself in the mirror."

ABC News Senior Congressional Correspondent Mary Bruce caught up with New Jersey Democrat Josh Gottenheimer.

"Can you explain your current thinking? Why undecided right now?" she asked.

"Because I made a commitment to my district from the moment that this began that I’m going to focus on all the facts," he said. "I’m gonna read everything, watch all the testimony and the hearings, read the transcripts, consult with scholars, and then of course talk to my constituents, and then make an ultimate decision. But until the final articles are released and they make a…and the committee makes a recommendation, I think it is premature to make a decision. And that’s what I committed to my district that I would do – to read everything, to look at all the evidence, make an evidence-based and evidence-driven decision, and that’s what I plan to do."

"What have you been hearing from your constituents?" Bruce asked.

"Frankly, we hear both sides -- those who are for, those who are against this. But I’ve heard from all my constituents, I’ve heard from most of my constituents the same thing – please follow the facts. Make sure you put the Constitution first, don’t let politics play into this. Do what’s best for the country. That I’ve consistently heard. And to make sure that I don’t make a … don’t pre-judge. I think I’ve heard that all along. Don’t pre-judge. And frankly I’ve heard that from Democrats and Republicans – please make a decision based on … a fact-driven decision," Gottenheimer said.

Rep. Anthony Brindisi of New York, who represents a Trump district, still hasn't made a decision.

"Right now I want to make sure the evidence fits these articles," he said.

Rep. Jeff Van Drew of New Jersey, one of two Democrats to vote against the resolution launching the impeachment inquiry, said he and Rep. Colin Peterson of Minnesota still plan to oppose both impeachment articles, but only thinks a few Democrats will join them.

"I think it's been pretty static," he said. "I wouldn't expect a huge number ... to vote no."

Van Drew he's hearing from constituents on both sides of impeachment. The breakdown of calls to his office is about 50/50 on the issue, he said.

"Whatever you do, you are going to aggravate people," he said, adding that he had seen "no" new evidence or testimony that could persuade him to vote for impeachment.