2020 Democratic presidential hopefuls Elizabeth Warren, Bernie Sanders battle for the liberal vote

WASHINGTON - Progressive White House hopefuls Massachusetts Sen. Elizabeth Warren and Vermont Sen. Bernie Sanders, who share similar visions, are battling for the support of liberal voters, a base they both share. 

Sanders is a democratic socialist who consistently draws some of the biggest crowds on the campaign trail. Warren, who is known for her policy prowess, famously said she “has a plan for that.” She is leading Sanders by two points, according to a new Fox News poll.

Last week, the Massachusetts senator answered the biggest policy question of her campaign by unveiling a detailed proposal to spend $20 trillion over 10 years to fund her single-payer health care plan.

The details of Warren's "Medicare for All" plan aim to quell criticism that the Massachusetts Democrat and presidential candidate has been vague about how she would pay for her sweeping proposal. Her refusal to say until now whether she would impose new taxes on the middle class, as Sanders has said he would, had become untenable and made her a target in recent presidential debates.

Late this week, New York Rep. Alexandria Ocasio-Cortez will make multiple campaign appearances alongside Sanders in Iowa. This comes just a month after the 78-year-old Vermont senator suffered a heart attack, which raised new concerns about his age and health. Her support is a reminder that Sanders remains a political force in 2020, even if he's viewed skeptically by the political establishment.

“I would say that Bernie and Elizabeth Warren certainly do not represent the establishment,” said Bob Shrum of the University of Southern California. “I mean, they are campaigning against it non-stop.” 

As the pair battle it out for the liberal wing of the party, it is unclear where their respective support would go if either candidate does not win the nomination. 

New polling shows that voters who are not supporting Warren would overwhelmingly select her as their second choice. 

But some voters who “feel the Bern” say their vote will go to Sanders and no one else. 

In general, both candidates share similar positions on Medicare for all, immigration and the economy. 

Some political observers say that both candidates’ staunch liberal views could hurt them in a general election. 

“They have a passionate primary constituency that has put them at the top of the polls,” said Dr. Ross Baker of Rutgers University. “But this same constituency, because of their expectations and demands that they have may be the kiss of death in a general election. Even against Donald Trump, a man whose popularity within the electorate has never been above 40 percent.”

The Associated Press and Stringr contributed to this report. This story was reported from Los Angeles.