NEW YORK (Reuters) - U.S. Democrat Hillary Clinton is the only presidential contender scheduled to attend a reception next week organized by a leading political association of Asian Americans and Pacific Islanders as she seeks to consolidate her support from minority voters.     The Asian Pacific American Institute for Congressional Studies Leadership Network, a nonpartisan group that seeks to get Asian Americans elected to political office, said on Wednesday that it had invited all presidential hopefuls to the event in Washington, but Clinton was the only one to accept. The campaigns of Clinton’s Democratic rival Bernie Sanders and Republican hopeful Ted Cruz did not commit, and the campaign of Republican front-runner Donald Trump campaign responded that he was unlikely to attend, Floyd Mori, president and chief executive of the leadership network said. Republican John Kasich’s campaign did not respond.     Minority voters have provided a boost to Clinton as she fends off a challenge from Vermont Senator Sanders for the Democratic nomination for the Nov. 8 presidential election. African Americans helped her notch key wins in states such as South Carolina and this week in Maryland.      Asian Americans and Pacific Islanders are a smaller group,  making up about 5.6 percent of the population, according to U.S. Census data. But in recent years they have been among the fastest-growing ethnic groups in the United States.     “We are a vote that is becoming increasingly powerful,” said Rep. Judy Chu, a Democrat in Congress representing California, who will introduce Clinton at the event. “In this election we are the swing vote in the swing states,” Chu said, pointing to Virginia and Nevada.     Still, challenges remain in building the Asian Americans electorate into a political force, Mori said.     “We are not as good at registering Asian Americans (to vote) as a lot of other populations,” he said. “We need to do better.”     