Speaker Nancy PelosiNancy PelosiTrump at rally says impeachment an 'attack on democracy itself' GOP lawmaker says House impeachment rules vote 'doesn't change anything for me' Overnight Health Care: Warren unveils 'Medicare for All' funding plan | Warren says plan won't raise middle class taxes | Rivals question claims | Biden camp says plan will hit 'American workers' | Trump taps cancer doctor Stephen Hahn for FDA chief MORE (D-Calif.) issued a stern warning to the 2020 Democratic primary field that progressive policies that might fire up the party’s liberal wing could prove damaging in the general election.

Pelosi said proposals such as “Medicare for All” and a wealth tax that have been touted by Sens. Elizabeth WarrenElizabeth Ann WarrenOvernight Health Care: Warren unveils 'Medicare for All' funding plan | Warren says plan won't raise middle class taxes | Rivals question claims | Biden camp says plan will hit 'American workers' | Trump taps cancer doctor Stephen Hahn for FDA chief O'Rourke ends presidential bid Five things to know about Warren's 'Medicare for All' funding plan MORE (D-Mass.) and Bernie SandersBernie SandersKrystal Ball: 'Manchin's refusal to back Bernie is particularly galling' Sanders, Ocasio-Cortez to hold climate summit in Iowa Overnight Health Care: Warren unveils 'Medicare for All' funding plan | Warren says plan won't raise middle class taxes | Rivals question claims | Biden camp says plan will hit 'American workers' | Trump taps cancer doctor Stephen Hahn for FDA chief MORE (I-Vt.) could appeal to progressive pockets but fail to land in key swing states.

“What works in San Francisco does not necessarily work in Michigan,” Pelosi said in an interview with Bloomberg News published Saturday. “What works in Michigan works in San Francisco — talking about workers’ rights and sharing prosperity.”

“Remember November,” she added. “You must win the Electoral College.”

While the California Democrat declined to endorse any candidate in the primary race, she unloaded on progressive policies, saying they fail to make inroads with swing voters who backed President TrumpDonald John TrumpTrump singles in on 'Sleepy Joe Biden' at campaign rally Trump at rally says impeachment an 'attack on democracy itself' GOP lawmaker says House impeachment rules vote 'doesn't change anything for me' MORE in 2016. 

“As a left-wing San Francisco liberal I can say to these people: What are you thinking?” Pelosi said. “You can ask the left — they’re unhappy with me for not being a socialist.”

The speaker specifically singled out Medicare for All as an example of a policy that may be beyond the pale for moderate voters the party will need to win back next year.

“Protect the Affordable Care Act — I think that’s the path to health care for all Americans. Medicare For All has its complications,” Pelosi said, adding that “the Affordable Care Act is a better benefit than Medicare.”

The comments come as Warren and Sanders remain in the top tier of the primary field, with the Massachusetts Democrat in particular laying claim to the title of front-runner in a series of national and early state polls.

The two progressives have fiercely defended their policies as bold proposals that are needed to shake up the status quo, hinting that their competitors’ policies fail to sufficiently restructure systems they slam as inequitable.

Warren tore into her critics Friday in defense of her Medicare for All plan after some Democrats voiced concerns over its cost.

“Democrats are not going to win by repeating Republican talking points and by dusting off the points of view of the giant insurance companies and the giant drug companies who don’t want to see any change in the law that will bite into their profits,” Warren fired back. 

“But if anyone wants to defend keeping those high profits for insurance companies and those high profits for drug companies and not making the top 1 percent pay a fair share in taxes and not making corporations pay a fair share in taxes, then I think they’re running in the wrong presidential primary," she continued.