Former Democratic presidential nominee Hillary Clinton appeared to signal support for a more moderate 2020 Democratic candidate, telling those in her party on Monday to support someone who can win the Electoral College vote.

Clinton famously won the popular vote in 2016 but lost the Electoral College and the presidency to Donald Trump. "We have to hope that whoever ends up being nominated can win the Electoral College," she said in Denver, according to The Hill. She added that a lot of Democrats' candidates can win the popular vote, but "as I know ... that's not enough."

Her comments came amid concerns that former Vice President Joe Biden's leading competitors could be too progressive to win in a general election. Specifically, Sen. Elizabeth Warren, D-Mass., has been gaining ground in polling for key states, but her ambitious and sweeping policies have raised concerns about electability.

JOY BEHAR SAYS ELIZABETH WARREN, OTHER DEMOCRATS, SHOULD DROP OUT OF 2020 RACE TO CLEAR PATH FOR JOE BIDEN

"I don't think we have a choice; we have to win," Clinton said on Monday.

In Iowa, Warren enjoys a slight edge, with Biden and Sen. Bernie Sanders of Vermont battling for second place with South Bend, Ind., Mayor Pete Buttigieg, who’s seen his poll numbers soar in recent weeks. The average of recent surveys from RealClearPolitics even shows Buttigieg narrowly holding the No. 2 slot over Biden.

And in New Hampshire, Warren enjoys the edge over Biden and Sanders, with Buttigieg in fourth place, according to the RCP average. In both states, Biden’s seen his numbers tumble since the summer.

Clinton's statement was the latest indication that Democrats preferred a candidate like Biden, a perceived moderate, as the nominee.

REINCE PRIEBUS HOPES WARREN WILL GET DEMS' 2020 NOMINATION: SHE AND HILLARY AREN'T 'LIKEABLE'

Many worried that Warren would alienate voters with her "Medicare for all" plan which would both end private insurance and cost around $52 trillion over the next decade.

House Speaker Nancy Pelosi, D-Calif., shared her concerns Friday about a government-run "Medicare-for-all" program, saying that she wasn't a "big fan" of the idea.

"I think that the affordable care benefits is better than the Medicare benefit but we have invited advocates for it to testify in Congress ... being respectful of the point of view," she added.

CLICK HERE TO GET THE FOX NEWS APP

"But it is expensive. Who pays is very important and what are the benefits that come in there? So, I would think that hopefully, as we emerge into the election year, the mantra will be more 'health care for all Americans' because there is a comfort level that some people have with their current private insurance."

Fox News' Paul Steinhauser contributed to this report.