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Senator Elizabeth Warren has ended her presidential campaign after a poor showing on Super Tuesday.
A favourite of the liberal left, the Massachusetts senator had been a frontrunner in the Democratic field.
However, Ms Warren, 70, failed to convert early excitement into votes.
The Democratic contest to take on President Donald Trump in November is now seen as a two-horse race between former Vice-President Joe Biden, 77, and Vermont Senator Bernie Sanders, 78.
Ms Warren's endorsement will be highly sought after by both candidates.
Her departure may clear the path for Mr Sanders in particular – the sole progressive candidate left in the race.
With Ms Warren's departure, a Democratic race that began with a record high of female candidates is now effectively left to two male front-runners.
Senator Warren called her supporters on Thursday to highlight what the campaign had already accomplished.
"We have shown that a woman can stand up, hold her ground, and stay true to herself – no matter what," she said. "We fundamentally changed the substance of this race."
What went wrong?
Now that she has dropped out, post-mortems on Elizabeth Warren's campaign have begun. Many point to her shifting message on universal government-run healthcare, a topic that was never a top priority for her. It caused liberals to stick with Bernie Sanders and centrists to have their doubts about her.
Others suggest she was harmed by hesitant performances in the debates that mattered – before the Iowa and New Hampshire contests. Her strongest effort came with her vivisection of Michael Bloomberg in Las Vegas, which was buried by Sanders's win in the Nevada caucuses – and too late to influence the outcome.
Then there's the issue of sexism. Four years after Democrats chose Hillary Clinton to be their nominee, voters may have been reluctant to opt for another woman atop the ticket. This reluctance was seldom explicit, instead being raised in concerns about "likability" or "electability" and what other, hypothetical, swing-state voters might think of her.
It also sometimes reared its head in Warren's media coverage, where her healthcare backtracking received considerably more criticism than similar pirouettes and hedging by Pete Buttigieg and other male candidates.
The US will elect its first woman president someday, but it will not be in 2020.
What does Elizabeth Warren believe in?
The erudite Ms Warren vaulted into the political arena more than a decade ago as she pushed for tougher regulation of the financial sector after the 2008 economic collapse.
She championed the creation of the Consumer Financial Protection Bureau – a government agency that would serve as a Wall Street watchdog.
In 2010, she helped the Obama White House set it up.
Two years later, the former Harvard law professor rode that momentum to a seat in the US Senate for Massachusetts.
Though her name was floated as a possible 2016 Democratic nominee, the senator demurred, sayingRead More – Source
