Pressed on whether she would endorse either Sanders or Biden, Warren said that was not happening today.
“Take a deep breath,” she said, urging supporters to take a couple of days to review their choices.
Warren's decision comes two days after she finished a distant third in her home state of Massachusetts, continuing a string of third and fourth place finishes which netted her a small number of delegates.
Maybe the biggest impact Warren had on the race was her attacks on billionaire Michael Bloomberg in his only two debates, as she punctured the growing aura of his candidacy, effectively starting his downward slide, which resulted in his withdrawal on Wednesday.
“A billionaire who calls women fat broads,” said Warren, as she called Bloomberg 'arrogant,' and spent much of his two debates tearing into the former New York Mayor repeatedly.
After an absolutely unprecedented reshuffling of the Democratic race over the last week - which resulted in big wins on Super Tuesday for Joe Biden - political experts weren't sure a Warren departure would have a big impact on a Biden-Sanders race.
Warren's decision came after a very disappointing showing on Super Tuesday - and in the first month of the Democratic race - as the Massachusetts Senator never finished above third place in any contest.
From the beginning, Warren set out to build a national campaign, energetically holding rallies and bubbling over with details about her many campaign ideas.
"I have a plan for that," she would say with a smile, as the audience would erupt into knowing applause.
“This is not the time for small ideas,” Warren told a crowd in New Hampshire.
While Warren trailed in the overall race, she still was drawing big crowds over the last two weeks.
But it never translated to the ballot box.
Her departure - on the heels of Tom Steyer, Pete Buttigieg, Amy Klobuchar, and Michael Bloomberg getting out of the race in the last six days - means the race effectively now boils down to Bernie Sanders and Joe Biden.
A new poll in Florida showed how the race has swung to Biden in recent days, as he jumped 27 points, to a 61-12 lead over Sanders - while Sanders and Warren basically stayed the same.