By Joseph Ax and Amanda Becker

(Reuters) – Elizabeth Warren ended her presidential campaign on Thursday, bowing to the reality that the race for the Democratic nomination has become a two-way battle between former Vice President Joe Biden and U.S Senator Bernie Sanders.

Warren, a liberal senator who won plaudits for her command of policy details, finished well behind the two front-runners on Tuesday in 14 states, including her home state of Massachusetts, leaving her path to the nomination virtually nonexistent.

Her exit ensures the contest is now a two-man race between moderate former Vice President Joe Biden and liberal U.S. Senator Bernie Sanders, who in many ways represent the main wings of the Democratic Party.

Warren, who still commands a loyal base of supporters, did not immediately endorse either of her rivals. When asked about an endorsement at a news conference on Thursday outside her home, she said she would decide whether to make one later.

“We don’t have to decide right this minute,” she said.

Warren also spoke bluntly about her failure to find a middle ground between the party’s dueling factions.

“I was told when I first got into this, there are two lanes,” she said. “I thought it was possible that wasn’t the case, and there was more room to run a different kind of campaign. Apparently that wasn’t the case.”

Warren’s departure leaves what had once been the most diverse field of candidates in U.S. history as a contest primarily between two white men with decades in office each nearing 80 years old.

Her relationship with Sanders may have been strained in January, when she accused him of calling her a liar on national television after he denied telling her in 2018 that a woman could not beat Republican President Donald Trump.

‘VICIOUS CYCLE’ ON ELECTABILITY

The vague notion of “electability,” a frequent buzzword on the campaign trail as Democrats prioritized defeating Trump over all other concerns, seemed to hurt Warren and non-white male candidates.

“The general narrative was that the women might be too risky, and I think there were people who heard that enough that it started showing up in polling … and becomes a vicious cycle that was hard to break out of,” said Christina Reynolds, vice president of communications at EMILY’s List, which works to elect women supporting abortion rights and had endorsed Warren.

Asked on Thursday about the role that gender played in the campaign, Warren said it was a tricky issue for female candidates to address.

“That is the trap question for every woman. If you say, ‘Yeah, there was sexism in this race,’ everyone says, ‘Whiner!'” she said, in front of her home in Cambridge, Massachusetts. “If you say, ‘No, there was no sexism,’ about a zillion women say, ‘What planet do you live on?'”

Warren said one of the hardest parts of leaving the campaign was knowing that millions of little girls would have to wait at least four more years before seeing a woman in the White House.

U.S. Representative Tulsi Gabbard remains in the race, but has repeatedly failed to win even 1% of the vote in primaries.

Meanwhile, Biden and Sanders continued to step up attacks on each other following Biden’s unexpectedly strong performance on Super Tuesday earlier this week.

The back-and-forth between the two contenders signaled a bruising battle to come as the race turns next to six states stretching from Mississippi to Washington state, which vote on March 10.

Sanders blamed the “establishment” and corporate interests for his losses in 10 of the 14 states that voted on Tuesday, a charge Biden called “ridiculous.”

“You got beaten by overwhelming support I have from the African-American community, Bernie,” Biden told NBC’s “Today” show on Thursday. “You got beaten because of suburban women, Bernie. You got beaten because of the middle-class, hardworking folks out there, Bernie.”

Biden received more support from black voters and women, particularly in suburban areas, exit polls found. Those two groups make up a substantial part of the Democratic electorate and were credited with delivering the party big wins during the 2018 midterm congressional elections.

Biden also pointed out that Sanders has raised more campaign cash, responding to criticism that his moderate rival is collecting money from corporate interests. Aside from candidates who have self-funded their campaigns, Sanders has boasted the largest cash hauls during this election. At the end of January, Sanders had raised $134 million while Biden raised $70 million.

Like Warren, Sanders has refused to hold fundraisers and instead relies on online donations. Biden, who has seen his online giving spike in recent days, regularly holds high-dollar fundraising events.

In addition to Mississippi and Washington state, voters in Michigan, Missouri, and Idaho on Tuesday. North Dakota will hold caucuses.

(Reporting by Amanda Becker in Washington and Joseph Ax in New York, additional reporting by Ginger Gibson in Washington; Editing by Scott Malone and Jonathan Oatis)