By Jonathan Allen
NEW YORK (Reuters) - Hillary Clinton met with black civil-rights leaders in New York City on Tuesday as she seeks to maintain a crucial edge in popularity among black voters over her Democratic rival for the presidency, U.S. Senator Bernie Sanders of Vermont.
"I thought that the secretary demonstrated an ease and familiarity with many of the issues we discussed this morning," Marc Morial, the president of the National Urban League, said after a two-hour meeting with former Secretary of State Clinton and a half-dozen civil rights groups at the league's headquarters.
He and other group leaders are due to hold a similar meeting with Sanders in Washington, D.C., on Thursday.
Clinton's campaign staff have long argued that surging support for Sanders will probably falter as voting for a party nominee moves to more racially diverse states in the coming weeks. Clinton's campaign says she has a longer record of working to solve problems that affect black people.
Sanders has said Clinton's polling lead among black voters is partly a result of her being much more famous than he is. He believes many non-white voters will be drawn to his message of fighting economic inequality as they get to know him.
Clinton's status as front-runner to be the Democratic nominee for the Nov. 8 presidential election was jolted this month when she beat Sanders by less than one percentage point in Iowa's caucuses, and lost to him by more than 20 points in New Hampshire's primary. More than 90 percent of people in those states are white.
The Reverend Al Sharpton, one of the country's best-known civil-rights activists, also joined the New York meeting, and joked warmly with Clinton in the corridors afterward, suggesting to gathered reporters that he had told her who he would endorse.
"My lips are sealed!" Clinton, who did not take any questions from the press, replied with a smile.
At a press conference later, Sharpton said Clinton was "candid and open" but also said he had yet to decide who to support and that no candidate should take the support of black voters for granted. "We are not a monolithic people," he said.
Both Clinton and her husband, former President Bill Clinton, have traditionally had solid support from African-American communities, a key component of the Democratic electorate. Opinion polls show Clinton with a strong lead over Sanders in South Carolina, where blacks are likely to make up more than half of the voters in the state's Democratic primary on Feb. 27.
Later on Tuesday, Clinton was heading to the historically black New York City neighborhood of Harlem to give a speech on breaking down the barriers that African-American families face, her campaign said.
Echoing issues that both she and Sanders raise while campaigning, Clinton was due to discuss her plans to reform the criminal justice system, which sends black men to prison in disproportionately high numbers.
Sanders also met with Sharpton earlier this month, and received an endorsement from Benjamin Jealous, a former chairman of the NAACP (National Association for the Advancement of Colored People) who said he could not support Clinton in part because of her support of the death penalty.
Clinton was endorsed by a political group associated with black members of the U.S. Congress last week. The Congressional Black Caucus Political Action Committee said Clinton had a long history of working on issues that affect black Americans.
(Reporting by Jonathan Allen; Editing by Frances Kerry)