Political analysts and party officials say they expect the race for Nassau County executive to test the power of the growing black, Hispanic and Asian communities transforming suburban Long Island.

Republican County Executive Edward Mangano is running for re-election against his predecessor, Thomas Suozzi, a Democrat who had won two terms to the office. Four years ago, Mr. Mangano unseated Mr. Suozzi by fewer than 400 votes.

This year, Democrats are working to turn out new minority voters to blunt the power of the county’s Republican machine. “Taking advantage of the demographic changes is the greatest challenge for the Suozzi campaign, and overcoming them is the greatest for Mangano,” said Lawrence Levy, executive dean of the National Center for Suburban Studies at Hofstra University.

A growing Caribbean population helped fuel a 17% increase in Nassau’s voting-age black population between 2000 and 2010, according to the Nassau County United Redistricting Coalition, a group that advocated for minorities in the county’s legislative-redistricting process. The Hispanic voting-age population grew 49% over that period, driven by Salvadoran and Guatemalan immigrants, according to the analysis. And the Asian voting-age population surged 68%, as South Asians settled in North Shore communities.

“We’re not in Levittown anymore,” said Daniel Altschuler, the coordinator of the Long Island Civic Engagement Table, a nonpartisan group trying to involve working-class minorities in politics. “People have this conception of Nassau County as this post-World War II, mostly-white suburb,” but demographics no longer bear that out, he said.

Nonwhite residents accounted for all the growth in Nassau between 2000 and 2010. The county remains mostly white, but the voting-age white population fell by 9% over that period.

The county’s growing diversity has coincided with a surge in Democratic registration. As recently as 2008, Republicans outnumbered Democrats by 15,000 in the county. In 2013, Democrats led by 40,000.

In 2011, Elmont and surrounding communities unseated their Republican Nassau County legislator and elected a Democratic Haitian-American candidate, Carrié Solages. In 2012, the community sent his sister, Michaelle Solages, to the state Assembly.

Party leaders and political observers say the county-executive race hinges on who can motivate their bases in a year without any national or statewide races on the ballot. Mr. Mangano had $1.2 million and Mr. Suozzi had $989,000 left to spend at the end of September, according to campaign-finance reports.

Jay Jacobs, county Democratic chairman, said his party was using data-gathering and “the biggest field operation we’ve ever had” to get out the vote. “The key to that demographic shift is to recognize that the challenge will be to get those people to believe this election is important to them, and to get them to vote,” he said. “They tend to be even-year voters.”

Republicans have to draw on the party’s legendary organization to counter the demographic tide, said Joseph Mondello, the Republican chairman. Before Mr. Suozzi won in 2001, Nassau hadn’t elected a Democratic county executive since the 1960s. “We have to try a little harder to try to get our job done, we have to raise more money,” he said. “The burden is getting heavier on the Republican Party, there’s no question about it, because of the demographics.”

Mr. Mondello said the party was trying to persuade minority voters that “maybe, just maybe, the Republicans are giving them something they haven’t been getting before.”

On a recent morning, Mr. Mangano gave a pep talk to GOP volunteers preparing to campaign door-to-door in Elmont, in the heart of Nassau’s growing Caribbean enclave.

Herve Duroseau, 30 years old, a sanitation worker and former boxing champion who is an executive leader in Mr. Mangano’s campaign, said the county executive’s down-to-earth presence and appearances at events had endeared him to the community. “For a long time, people have been just saying they’re Democrats,” Mr. Duroseau said. “I ask them, ‘Why? What have they done to deserve that?’ They take our vote for granted. It’s disrespectful.”

Later that day, Mr. Suozzi ate barbecue and nodded to music at the opening of a Democratic headquarters in New Cassel, a community of mostly black and Hispanic residents. “When Suozzi left, it was for change. People want change again,” said Norman Sutton, 60, of Westbury, a school custodian who said he supported Mr. Suozzi.

Mr. Suozzi’s effort to court minority voters has proved complicated. The Corridor Counts, a new group formed by black and Hispanic leaders, campaigned for Mr. Suozzi’s primary opponent. The group declined this week to endorse either Mr. Suozzi or Mr. Mangano. Frederick Brewington, a Hempstead civil rights attorney who is a leader of the coalition, said Messrs. Suozzi and Mangano have similar records of neglecting issues like high foreclosures rates, gun violence and failing schools in minority neighborhoods.

“The Republicans pretty much abuse and neglect us,” said Sergio Argueta, a Uniondale social worker who is another of the group’s leaders. “But the Democrats take us for granted.”

Mr. Suozzi’s campaign declined to comment on the group’s decision.

Democrats also say Republicans recruited a former Freeport Village mayor, Andrew Hardwick, to run on a third-party line in order to siphon black and Hispanic votes from Mr. Suozzi. Mr. Hardwick and Republicans denied the charge. Mr. Hardwick is fighting in an appeals court to remain in the race after Democrats successfully challenged his ballot signatures.

To view the original article, click here.