CAMBRIDGE, Mass. – Sen. Elizabeth Warren is taking her time.

The progressive lawmaker from Massachusetts, standing outside her home on Thursday as she announced that she was ending her White House bid, said “not right now” when asked if she will be endorsing either of the two remaining major Democratic presidential candidates: former Vice President Joe Biden or her fellow populist champion Sen. Bernie Sanders of Vermont.

“Not today. I need some space around this and want to take a little time to think a little more,” Warren emphasized.

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And she stressed that she’d tell supporters of her campaign who didn't know who to back now to "take a deep breath and spend a little time on that," and that they "don't have to decide this minute.”

Adam Green, co-founder of the pro-Warren Progressive Change Campaign Committee, highlighted that "there’s no more important endorsement for the two remaining candidates than Elizabeth Warren’s."

Green said his group "will be with her as she thinks about her next steps."

Both Biden and Sanders are hungry for an endorsement from Warren – and both candidates held phone conversations with Warren on Wednesday.

Sanders, speaking in Vermont to reporters soon after Warren’s announcement, said he’d “love to have her endorsement” and made the point that he was much closer to Warren ideologically than the more moderate Biden.

“Today what I am doing is reaching out to the millions of strong supporters she had and to tell them that you know while Senator Warren and I had nuances of differences, we did, that there was no question that her agenda -- what she fought for in the campaign -- was far closer to what I am fighting for than what Joe Biden believes in and we would welcome those supporters,” he said.

But in dropping out, Warren explained that she didn’t belong to either the Biden or Sanders lanes.

"You know, I was told at the beginning of this whole undertaking that there are two lanes. A progressive lane that Bernie Sanders is the incumbent for and a moderate lane that Joe Biden is the incumbent for and there's no room for anyone else in this. I thought that wasn't right, but evidently, I was wrong,” Warren explained.

Warren, once a co-front-runner along with Biden in the late summer and early autumn, had seen her fortunes slip in October and November amid attacks from her rivals and more scrutiny about her plans to implement and pay for a government-run Medicare-for-all health care system. And she her hopes of winning the nomination plummeted after lackluster finishes last month in New Hampshire’s primary, the Nevada caucuses, and last weekend’s South Carolina primary.

The final straw was her poor performances on Super Tuesday - when 14 states from coast to coast held primaries. Her dilemma was best illustrated by a third-place finish in Massachusetts, her home state.

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Three more establishment-type candidates who dropped out the past four days – former New York City Mayor Mike Bloomberg, former South Bend, Ind., Mayor Pete Buttigieg, and Sen. Amy Klobuchar of Minnesota -- all backed Biden as traditional Democrats rallied around the former vice president. But so far that’s not happening among progressives.

“Warren’s endorsement would have meant the most for Sanders if she endorsed before Super Tuesday, to show progressives are able to coalesce around a candidate the way the moderate wing did for Biden. That doesn’t mean an endorsement of Sanders doesn’t have value. But it’s been weakened by Sanders inability to compromise and negotiate with his opponents,” argued Democratic strategist Michael Ceraso.

Ceraso, a veteran of Sanders’ 2016 presidential campaign as well as Buttigieg’s 2020 White House bid, spotlighted that Warren “could be the candidate to put a close to Sanders’ candidacy if she endorses Biden. That could end the primary sooner, and give her a larger voice in Biden’s general election strategy.”

Battle for Michigan heats up

Michigan has the most delegates up for grabs and is arguably the most important of the six states holding primaries next Tuesday, March 10.

With so much riding on the line in Michigan, Sanders on Thursday canceled a campaign stop scheduled for Friday in Mississippi -- another March 10 state -- and instead said he would travel to Michigan.

"We are bringing more staff into Mississippi," he told reporters.

But he emphasized that "Michigan is where we'll spend a bit of our time."

Sanders was swept by Biden in all five of the southern states that voted on Super Tuesday.

His move came hours after Biden landed the backing of the Michigan's governor.

Democratic Gov. Gretchen Whitmer announced on Thursday that she is endorsing the former vice president, saying in a statement that “working families in Michigan need a president who will show up and fight for them, and Joe Biden has proven time and again that he has our backs.”

The latest poll in the state – Detroit News/WDIV-TV survey conducted before Biden’s big night on Super Tuesday when he swept 10 of the 14 primaries – indicated the former vice president is topping Sanders by 6 percentage points.

Sanders -- who’s making his second straight presidential run – defeated eventual nominee Hillary Clinton in the 2016 Democratic primary in the state, thanks to a last-minute upset win. That foreshadowed Clinton’s narrow loss to Donald Trump in the November 2016 general election in Michigan. Trump’s victory with working-class white voters in the state, as well as narrow wins in two other crucial Rust Belt states -- Pennsylvania and Wisconsin -- propelled him into the White House.

Campaign cash surge

Both the Biden and Sanders campaigns were hauling in campaign cash coming out of Super Tuesday.

The Sanders campaign reported bringing in $5.5 million Tuesday night through Wednesday from 220,000 contributions. And Biden’s campaign touted that it hauled in $7.1 million on-line Tuesday through Wednesday.

While the Sanders campaign has long been successful raising large amounts of money through a massive amount of small-dollar grassroots donations, Biden’s campaign struggled with fundraising until the floodgates opened in the wake of his landslide victory in Saturday’s South Carolina primary.

Bloomberg lends a helping hand

One day after he suspended his own White House bid, former New York City Mayor Mike Bloomberg launched a new independent expenditure group with a mission to support the eventual Democratic presidential nominee defeat President Trump in November’s general election.

Fox News’ Kelly Phares reports that Bloomberg aides confirm the new organization will include field offices in six crucial battleground states all won by Trump in 2016: Arizona, Florida, Michigan, North Carolina, Pennsylvania, and Wisconsin. Aides said that the name of the group, as well as its budget and scope, are all forthcoming.

Bloomberg – a multibillionaire business and media mogul -- said even before he launched his White House bid in November that he would spend freely to defeat Trump in the 2020 general election even if he didn’t win the Democratic nomination.

Bloomberg also released his first digital spot since dropping out of the race on Wednesday. The video – titled "Dump Trump" -- features famous movie clips spliced together with video of the president talking about the 2020 Democratic presidential contenders.

Fox News' Tara Prindiville, Andrew Craft, and Kelly Phares contributed to this report