WASHINGTON/NEW YORK (Reuters) - U.S. Democratic presidential candidates took aim on Thursday at a rival whose name has not yet appeared on the ballot in the early voting states but whose television ads have blanketed the airwaves: billionaire former New York Mayor Michael Bloomberg.

Former Vice President Joe Biden and Senator Elizabeth Warren of Massachusetts, who lagged in the first two nominating contests in Iowa and New Hampshire, targeted Bloomberg over past policing tactics in the largest U.S. city and his comments about a mortgage practice widely seen as racially discriminatory.

Biden did a quick swing through New York City, where he headlined a pair of high-dollar fundraisers and vowed he would win the nomination despite his slow start in early voting.

Democrats are vying to face Republican President Donald Trump in the Nov. 3 election. Other candidates headed to Nevada, where reaching Latino voters and winning union support will be key to success in the state’s caucus on Feb. 22.

Below are highlights from the campaign trail on Thursday:

BIDEN ON THE MONEY TRAIL

Ahead of a weekend visit to Nevada, Biden’s fundraisers in midtown Manhattan on Thursday evening raised what one donor said was close to $800,000.

Biden acknowledged coming up short in Iowa and New Hampshire but emphasized that 98 percent of voters had yet to weigh in - including, black voters in more diverse states who have consistently supported Biden in opinion polls.

“I’m confident we’ll win South Carolina. I think we’ll win or be in a very tight race, one or two, in Nevada,” Biden said of the next two states to vote.

Biden’s poor showing has dented his early status as the campaign front-runner.

But he said his base of support - African Americans and working-class voters with a high-school education - made him the favorite on March 3, Super Tuesday, when 14 states weigh in.

Biden took aim at leading rival Senator Bernie Sanders, questioning the viability of his Medicare for All proposal, and asking if down-ballot Democrats in battleground states would be happy having a self-described democratic socialist at the top of the ticket.

“I’m the only one running that has ever gotten big things done,” he said.

ON TO NEVADA

Several candidates headed to Nevada late Thursday for a week of campaigning ahead of its nominating caucus. Former South Bend, Indiana, Mayor Pete Buttigieg, Minnesota Senator Amy Klobuchar and billionaire progressive activist Tom Steyer fielded questions from the audience at a presidential forum in Las Vegas held by the League of United Latin American Citizens, which calls itself the largest and oldest Hispanic organization in the United States. Sanders addressed the group by video link.

Klobuchar told the group of her grandfather’s travails immigrating from Switzerland at a time when there were quotas on Swiss immigrants, while Buttigieg, who speaks several languages, answered questions that were put to him in Spanish. Unlike largely white and rural Iowa and New Hampshire, the earliest states to hold nominating contests, Nevada’s population is nearly 30% Hispanic or Latino, 10% black and 9% Asian, according to the U.S. Census, highlighting the need to win support in diverse communities.

NEVADA UNION WILL NOT ENDORSE

Nevada’s largest labor union, Culinary Workers Local 226, said it would not endorse any of the eight leading Democrats ahead of its state’s caucuses, de-escalating a war of words with Sanders, who finished first in this week’s New Hampshire primary.

The 60,000-member union, with outsized influence in a state heavily dependent on tourism, opposes Sanders’ proposed government takeover of healthcare funding, amid fears of losing members’ hard-won union health coverage.

The union’s criticism of Sanders’ plan in recent days raised the possibility it would endorse a centrist like Biden.

The Las Vegas Weekly endorsed Biden and fellow Democrat Klobuchar, both moderates.

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Houston Mayor Sylvester Turner, U.S. Representative Ted Deutch of Florida and former North Carolina Governor Bev Perdue all endorsed Bloomberg.

TARGET BLOOMBERG

Biden said he planned to debate Bloomberg on his record on racial discrimination, while Warren slammed his past defense of a discriminatory housing practice known as redlining.

Bloomberg, who is self-financing his campaign, has come under fire for comments he made in 2008 that tied a collapse in the U.S. housing market to a ban on redlining, in which banks decline to make mortgage loans to entire neighborhoods.

“Once you started pushing in that direction, banks started making more and more loans where the credit of the person buying the house wasn’t as good as you would like,” Bloomberg said in remarks that resurfaced in a report by the Associated Press.

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“We need to confront the shameful legacy of discrimination, not lie about it like Mike Bloomberg has done,” Warren wrote on Twitter.

Biden told ABC’s “The View” he would challenge Bloomberg on the matter and on Bloomberg’s past support for a policing strategy known as “stop and frisk” that ensnared disproportionate numbers of blacks and Latinos during Bloomberg’s mayoral tenure.

Bloomberg has not yet qualified for next Wednesday’s Democratic debate in Nevada. He is not competing in Nevada or South Carolina, which votes on Feb. 29.

The Bloomberg campaign declined to comment on Biden’s and Warren’s statements. Bloomberg apologized for stop and frisk in November a few days before announcing his candidacy.

BLOOMBERG TAKES AIM AT TRUMP

Bloomberg drew crowds of hundreds in North Carolina, one of the states that vote on Super Tuesday, where he will first appear as a declared candidate.

At a coffee shop in Winston-Salem, Bloomberg said he was not afraid of Trump.

“I am a New Yorker. I know how to deal with New York bullies,” he said.

Trump on Thursday lobbed a fresh series of insults at Bloomberg, calling him a “loser” on Twitter.

Bloomberg’s personal fortune, estimated at about $60 billion, dwarfs that of the president.

Several voters in the crowd in Winston-Salem said they wanted a moderate candidate who could beat Trump in November. Some said they were looking for an alternative to Biden after becoming concerned by his debate performances and weak showings in the first two voting states.

Cassaundra El-Amin, a black voter, said she was concerned about Bloomberg’s stop-and-frisk policy but felt his apology was sincere.

“I just feel like he might be able to beat Trump,” she said.