Washington (CNN) A new storm is brewing inside the Democratic Party as competing factions begin to grapple for its leadership as the party reels in the wake of Donald Trump's stunning victory.

The emerging favorite to fill the job, Minnesota Rep. Keith Ellison, made formal his candidacy for the chairmanship on Monday, saying the party must "begin the rebuilding process now."

In what might be perceived as a jab at the broader Democratic strategy in 2016, he said the party "did not motivate enough people to the ballot box" in the past election and, given the Democrats' struggles up and down the ballot, that he would seek to "build a bench not just for federal candidates, but for state and local candidates across the nation."

Ellison, the first black Muslim elected to Congress, enters the contest with the backing from across the left. He's won endorsements from Sen. Bernie Sanders, the fiery independent and former Democratic primary candidate, along with outgoing Senate Minority Leader Harry Reid and Sen. Chuck Schumer, who is set to replace Reid in 2017, all pledging their support.

But other politicos have expressed interest in the position.

Howard Dean, who ran the Democratic National Committee from 2005 to 2009, and announced last week he would again seek its top role, and is expected to be among Ellison's most formidable challengers.

Another former presidential candidate, Martin O'Malley, has also announced that he is throwing his hat in the ring.

"Since the election, I have been approached by many Democrats who believe our party needs new leadership," said the former Maryland Governor. "I'm taking a hard look at DNC Chair because I know how badly we need to reform our nominating process, articulate a bold progressive vision, recommit ourselves to higher wages and a stronger middle class, and return to our roots as a nationwide, grassroots party."

New Hampshire Democratic Party Chairman and DNC Vice Chair Ray Buckley is exploring a run, according to the Boston Globe.

".@ChairmanBuckley on DNC chair, not officially running yet, but "I am definitely being strongly encouraged to consider it by DNC members," reporter James Pindell tweeted.

.@ChairmanBuckley on DNC chair, not officially running yet, but "I am definitely being strongly encouraged to consider it by DNC members." — James Pindell (@JamesPindell) November 11, 2016

In an interview with CNN affiliate NH1 , Buckley said he had received a number of calls and emails from people "all over the country" encouraging him to run.

"In the last few days there have been a lot of people calling in from all over the country, either emailing me or picking up the phone, that have expressed great interest in being able to essentially flip the DNC upside down and restructure how it operates, how it works making it much more grassroots friendly organization and less of a top to bottom organization," Buckley said.

And Labor Secretary Tom Perez, an outspoken surrogate of Hillary Clinton, is eyeing a run, according to Democrats with knowledge of his plans. A number of Democrats -- especially those interested in someone who can rally the party together after Tuesday's crushing loss -- are floating his name and Perez is said to be receptive, according to people close to him. One upside to Perez, according to people close to him, is that he has limited experience in elected office, something a number of DNC members have raised as red flags for other contenders.

Sanders backing Ellison

But Sanders -- a registered independent who caucuses with Democrats and fought a lengthy primary battle for the party's nomination this year -- and top allies are touting Ellison for the job. The Minnesota congressman currently co-chairs the Congressional Progressive Caucus.

In an email to supporters late Thursday, the Vermont senator said Ellison was uniquely qualified to take on "the political establishment and billionaire class," and that "his experience and perspective would be key to leading the fight against Trump."

Sanders also made the case for the institutional value of the DNC, an organization he and his backers clashed with repeatedly during the primaries.

"I'm sure a lot of you have some feelings about the Democratic National Committee," he said. "The truth is that it is an important entity to build, support, and maintain if we are to have the chance to organize and win in the coming elections while Trump is president."

Ellison supported Sanders in the primary, but emerged as a vocal Clinton supporter after she clinched the nomination. Sanders named Ellison to the Democratic convention's platform drafting committee this summer, filling an influential slot given to the Vermont senator as a concession from the party after an unexpectedly tense nominating contest.

On Sunday Ellison also won the backing from Senate Minority Leader Harry Reid, who is retiring from Congress after the turn of the year.

"My friend Keith Ellison is a terrific leader and a strong progressive who knows how to get things done," Reid said in a statement. "Now is the time for new thinking and a fresh start at the DNC. Now is the time for Keith."

Ellison's office refused to comment to CNN on the record, but he said on a Democracy For America call late Thursday that he would make an announcement about his intentions on Monday.

Dean eyes return

A former governor of Vermont, Dean served as head of the DNC following his own insurgent, though ultimately unsuccessful bid for the party's 2004 nomination. As part of his leadership, Dean championed a "50-state strategy," a plan intended to broaden the electoral map for Democrats.

"The dems need organization and focus on the young," Dean tweeted on Thursday, proposing to renew the strategy. "Need a fifty State strategy and tech rehab. I am in for chairman again."

The dems need organization and focus on the young. Need a fifty State strategy and tech rehab. I am in for chairman again. — Howard Dean (@GovHowardDean) November 10, 2016

On Friday, Dean stepped down from his special adviser role at Democracy for America, a progressive political action committee he founded in 2004.

But Dean, despite his considerable ties to the more liberal wing of the party, looks to be in for a struggle against a progressive left emboldened by Sanders' primary bid.

On Thursday night, People for Bernie, a tech-savvy progressive group with ties to Sanders, told CNN it was backing Ellison as a first step in displacing Clinton loyalists with "a leadership untainted by cozy relationships to Wall St. moneymen, corporate behemoths, dictators, or monarchs."

In a jab at Dean, People for Bernie co-founder Charles Lenchner added, "Any 50-state strategy must begin with a 50-state accountability project; we reject any effort to unite the party behind the agents of a failed leadership."

The current head of the DNC is Donna Brazile, a longtime Democratic operative and former CNN contributor, who is leading in an interim capacity after Debbie Wasserman Schultz resigned on the eve of the convention. Hacked emails appeared to show Wasserman Schultz and other since-departed DNC officials discussing ways to undermine Sanders' effort to oust Clinton in the primary.

Brazile has come under increasing scrutiny after another trove of hacked emails showed her forwarding questions from a town hall jointly hosted by CNN to the Clinton campaign.