Less than three weeks before the first votes are cast in Iowa only three non-white Democratic presidential candidates remain.

WASHINGTON  The 2020 Democratic presidential field has been heralded as the most diverse in history.
It at times has included a Latino man, an Asian American man, a Samoan American woman, three black men and one black woman. In addition to its racial and ethnic diversity, the field also included a gay man and a record number of women.
But less than three weeks before the first votes are cast in Iowa  and after Sen. Cory Booker dropped out Monday  only three non-white Democratic presidential candidates remain: former Massachusetts Gov. Deval Patrick, Rep. Tulsi Gabbard and entrepreneur Andrew Yang.
The Democratic Party tried to evolve this year. It still has some work to do, said Keneshia Grant, a political scientist at Howard University and author of an upcoming book, The Great Migration and the Democratic Party.
It has to figure out how it can be a party that makes space for people who look like their most important constituency to hold the big offices or even having a chance to hold the big offices,” she said. “Its a sad day, a day that we saw coming, but sad no less that we didnt end up with a candidate of color in the party that is home to people of color.”
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Black, Latino and Asian American voters are key to Democratic electoral victories and overwhelmingly vote Democratic.
In 2018, 90% of black voters said they voted for Democratic candidate in the race of the House of Representatives, according to Pew Research Center. Among Asian voters, 77% said they voted for the Democrat, while 69% of Hispanic voters said they went for the Democratic candidate. 
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Fundraising woes plague candidates of color
Booker, former Housing and Urban Development Secretary Julián Castro and Sen. Kamala Harris all cited fundraising issues when they ended their campaigns. 
Our campaign has reached the point where we need more money to scale up and continue building a campaign that can win money we dont have, and money that is harder to raise because I wont be on the next debate stage, Booker wrote in an email to supporters Monday.
Harris in an email to supporters when she dropped out last month said her campaign for president simply doesnt have the financial resources we need to continue. 
“Im not a billionaire, Harris said in the email. I cant fund my own campaign. And as the campaign has gone on, its become harder and harder to raise the money we need to compete.
Grant said another challenge for the party is holding the early primaries in states like Iowa and New Hampshire. Castro in November made the lack of diversity of the two early voting states a key part of his pitch to voters, saying they’re “not reflective of the diversity of our country, and certainly not reflective of the diversity of the Democratic Party.”
MSNBC national correspondent Joy Reid hinted at some of those same sentiments Monday.
At some point shouldn’t the Democratic Party which is the party preference or lean of most people of color figure out a way to not let state voting order and money reduce the options its voters have for president? she wrote on Twitter shortly after Booker announced he was ending his campaign.
Grant also pointed to the debate thresholds in particular as a factor for candidates of color. 
Despite meeting the donation threshold necessary, Booker and Castro both failed to qualify for December Democratic debate due to low poll numbers. Harris did make it to the December debate stage, but dropped out about two weeks before. 
Some candidates of color tried to fight back against the criteria.
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Yang was the only non-white candidate to make it to the debate stage in December. Last month, he called on the Democratic National Committee to commission additional polls in an effort to make the debate stage more diverse.
“With the upcoming holidays and meager number of polls currently out in the field, a diverse set of candidates might be absent from the stage in Des Moines for reasons out of anyone’s control,” Yang wrote to DNC Chairman Tom Perez in a letter dated Dec. 21.
The DNC denied to commission polls, saying it has been “more than inclusive throughout this entire process. Yang didnt make the polling mark for the debate. Every candidate on the debate stage Tuesday is white.
Who is getting the support of voters of color?
Despite the historic diversity among the candidates, voters of color largely have not flocked to candidates of the same race or ethnicity.
Among black voters, Booker was netted 4% in a recent Washington Post-Ipsos poll. Former Vice President Joe Biden led with black voters in that poll, earning 48% support, followed by Sen. Bernie Sanders with 20%. Warren trailed at 9%, according to the poll.
When Harris was still in the race, she also struggled to gain traction with black voters. Some progressives criticized Harris for her record as California attorney general, arguing she was part of an era of “tough on crime” Democrats. 
And Castro struggled to gain support from Latino voters. Only 2% of Hispanic Democratic voters said they support Castro, according to a Noticias Telemundo poll conducted in late October. Biden led with 26%, followed by Sanders at 18% and Warren at 10%.
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Grant said some black voters are making a calculation that they want to win above anything else, which means supporting candidates like Biden. Biden has touted his role as vice president to President Barack Obama, who is still widely popular among black voters. Grant said Biden is seen by many black voters as the pragmatic choice.
And unlike Obama, she said, Booker and Harris lacked the resources and ground game to pull off a win in Iowa. 
They couldnt fight back against this idea of pragmatism or Joe Biden being the only pragmatic (candidate) because they didnt have the money to play the game, she said.