(CNN)As the House Judiciary Committee held its first impeachment hearing into President Donald Trump this week, some of the House's most vulnerable Democrats privately huddled to discuss how to protect their majority.
At the headquarters of the House Democrats' campaign arm, they talked about what they were hearing back home and were briefed on an internal poll surveying 57 battleground districts from October to November, according to a source familiar, which showed support for impeaching and removing Trump had stayed about the same — slightly trailing the opposition — despite a Republican onslaught. While independents had surged to support it, Republicans had rallied around their party leader.
While the polling was meant to reassure Democrats from highly competitive districts, they are still uneasy about the historic vote they're about to cast, which could have major ramifications for the country and their races.
"I'm totally undecided," Rep. Anthony Brindisi of New York, a freshman from a competitive district who had initially resisted an impeachment inquiry, said Friday. "Anytime you talk about impeaching a president -- the third time in our nation's history -- that's a very serious vote. I take it very seriously."
The day after the briefing, Speaker Nancy Pelosi announced the House would proceed with articles of impeachment, setting up a vote that will present a tricky choice for the 31 Democrats in Trump districts.
Hours later, Brad Parscale, the Trump campaign manager, tweeted that "impeachment is killing" freshman House Democrats — "and polling proves it." He then tweeted an internal poll showing that in Oklahoma Rep. Kendra Horn's district, less than half of respondents support impeachment — a surprisingly high number there, but one that still showed that a slim majority of her constituents did not want her to vote to impeach the President.
Like many other Democrats in red districts, Horn told CNN that she's still deciding on how to vote, waiting to see "all the information," including how the articles of impeachment will be written.
The charges laid out during Wednesday's hearing include abuse of power and bribery, obstruction of justice and obstruction of Congress. Democrats say Trump put his personal interest over the country's when he pressured Ukraine to announce politically-damaging investigations of Democrats, while using military aid and a White House meeting coveted by Ukrainian leader Volodymyr Zelensky as leverage.
Some Democrats hope that their colleagues do not expand the articles further, or include episodes of alleged obstruction of justice found in the Mueller report in the articles.
On Friday, several freshmen Democrats bluntly warned their leadership not to include evidence from the Mueller report in the articles of impeachment. Their argument: They only got behind an impeachment inquiry because it was narrowly focused on Ukraine -- and didn't believe the evidence that Trump sought to derail an investigation into his presidency and the 2016 campaign were sufficient grounds for impeachment.
"No," Brinidisi said flatly when asked if he'd be inclined to support an article that includes Mueller evidence. "I'm going to see what the articles are that are put on the floor. ... It's my job to decide whether that evidence fits those articles of impeachment."
California Rep. Gil Cisneros said Democrats "need to stay focused on Ukraine," citing how he and a group of more moderate members endorsed an impeachment inquiry after Trump's actions with Ukraine prompted national security concerns. "It was about Ukraine, and the President putting our national security at risk. That's what I'm ready to vote on."
But few of these Democratic members really want to debate what should or should not be included in articles — they'd rather not talk about this at all. Horn said her constituents are primarily concerned about education, funding the government and health care, calling prescription drug pricing "one of the biggest issues that comes up just over and over and over again."
"It's an ongoing question, but it's also not the only thing that's happening," she said of impeachment.
The members have grown tired of a media that is covering all developments of the impeachment inquiry. When a CNN reporter approached him on Friday, Rep. Joe Cunningham of South Carolina said he'd like to discuss the United States-Mexico-Canada Agreement, before duly fielding questions from a number of reporters on impeachment.
Cunningham said the allegations against Trump are "very serious" but wasn't sure how he'd vote until he saw the articles.
"I wasn't elected to impeach the President," he added. "And I also wasn't elected to protect the President."
Republicans are predicting that the impeachment vote will flip the House. On Thursday, Rep. Tom Emmer, the chair of the National Republican Congressional Committee said, "House Democrats' unhealthy obsession with trying to remove the President of the United States from office and undo the 2016 election will cost them their majority next year."
For weeks, the Republican political groups have worked to make that happen. Last month, the conservative American Action Network launched a $7 million television and digital ad campaign directed at Rep. Max Rose of New York and other House Democrats in Trump districts.
Rose dismissed the notion that the vote will be politically difficult for him.
"Nothing we do here is difficult," said Rose. "Nothing we do here is hard. I've got cops and I've got firemen going and risking their lives each and every day in New York City. We got soldiers in combat right now. That's hard. None of this is difficult, alright? This is cushy s---."
