Nicole Gaudiano

USA TODAY

WASHINGTON – Now comes the real test for Sen. Bernie Sanders.

The Vermont independent, after trouncing Hillary Clinton in Tuesday’s Democratic presidential primary in New Hampshire, must prepare to face more diverse electorates as he turns to contests in Nevada on Feb. 20 and South Carolina on Feb. 27.

Top takeaways from the New Hampshire primary

Sanders has momentum after finishing just 0.3 points behind Clinton at the Iowa caucuses and crushing her by more than 20 points in New Hampshire. But it’s unclear if his performance in those predominantly white states will provide him with enough momentum to overcome the former secretary of state's name recognition and long-standing support among African American voters in later nominating contests. Black voters are expected to comprise more than half the electorate in South Carolina's primary.

“The results of the last two weeks combined showed he’s a viable candidate,” Robert Oldendick, a University of South Carolina political science professor, said of Sanders. “It will cause the Democratic primary voters here to take him a little more seriously, take a closer look at him. But … Clinton’s lead is very solid.”

Bernie Sanders seeks to expand appeal to South Carolina and beyond

Clinton flashbacks to 2008 may end after Iowa

Clinton led Sanders more than two-to-one in a Jan. 17-23 NBC News/Wall Street Journal/Marist South Carolina poll. Her 64-27% advantage over Sanders among likely Democratic primary voters was largely due to backing from 74% of African-American likely voters, compared to 17% for Sanders.

Nationally, Clinton also leads Sanders among Latinos, who will play a prominent role at the Nevada caucus. Most Southern states holding nominating contests on March 1 also have sizable minority populations.

"Hillary understands the concerns of our communities and won't make promises that she can't keep," South Carolina state House Minority Leader Todd Rutherford said in a Wednesday statement after endorsing Clinton. "Unlike Bernie Sanders, Hillary isn't new to issues facing African Americans. She understands the hard truths about systemic inequality that still exists in too many of our cities."

Sanders, who has represented mostly white Vermont in Congress for two decades, has rallied young people with his calls to end the “rigged economy” that he says is maintained by a corrupt campaign finance system. But he says his "political revolution" will bring together people of all races.

Sanders has worked to expand his appeal in the South by focusing on the need to combat poverty in the African-American community and "institutional racism." He became more vocal and specific on those issues as he faced protests last summer from Black Lives Matter activists, who disrupted his speeches with demands for criminal justice reforms.

Sanders notes that he participated in the historic March on Washington for Jobs and Freedom as a young college student and was arrested while protesting public school segregation in Chicago.

"The reason we’ll do well is our views on criminal justice in this country," Sanders said Wednesday on ABC's The View. "We have a broken criminal justice system. Why should we in America have more people in jail, largely African-American and Latino, than any country on Earth?"

In November, Sanders launched Spanish-language radio ads in Nevada along with ads on African-American radio stations in South Carolina, including one that emphasizes his fight to end “institutional racism” and reform the criminal justice system. He followed up later with TV ads in both states.

His efforts helped him secure endorsements from several black leaders, including former NAACP President and CEO Ben Jealous, and a handful of African-American South Carolina state lawmakers. Those include Rep. Justin Bamberg, who switched his endorsement from Clinton to Sanders. Bamberg is a lawyer for the family of Walter Scott, a black man who was fatally shot by a white South Carolina police officer last year.

"They have a pretty potent ground operation going on in South Carolina," Rep. James Clyburn, the state's only Democrat in Congress and the highest-ranking black member of the House, said on MSNBC Wednesday.

Clyburn left open the possibility of making an endorsement after this week. He predicted the battle for the Democratic nomination could last until June.

On Wednesday morning, Sanders had breakfast at Sylvia's restaurant in Harlem, N.Y., with the Rev. Al Sharpton, a civil rights activist who hosts an MSNBC show and is president of the National Action Network. Sharpton ate with then-Sen. Barack Obama at the restaurant in 2007 while Obama was campaigning for the presidency.

"The focus was to deal with the litany of issues that African-American and Latino voters are facing," Sharpton told MSNBC after the meeting. Those issues include criminal justice issues, economic disparities and the lead-tainted water crisis in Flint, Mich.

Sharpton declined to make an endorsement, but said, "I thought it was very important and significant that on the morning after his huge victory in New Hampshire, he would come to Harlem and have this meeting."

Sanders says N.H. win 'will echo from Wall Street to Washington'

Sanders' spokesman Michael Briggs said Sanders has already been tested, coming from 40-50 percentage points behind Clinton at the beginning of the campaign to a "dead heat" in Iowa and winning New Hampshire in a "landslide of historic proportions."

Sanders won in New Hampshire by the second-largest margin in a contested Democratic New Hampshire primary, behind only John Kennedy’s 1960 win over pen inventor and political novice Paul Fisher, according to an analysis by University of Minnesota's Smart Politics blog.

In the 18 hours since the polls closed, Sanders raised more than $5.2 million, breaking his record for money raised in less than a day, according to the campaign.

"The results in those two places are going to give us a slingshot effect as we go into other states in terms of just his recognition around the country," Briggs said. "The more people who know about Bernie, the better they like him and the ideas that he’s talking about."

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