Julian Castro, the U.S. Housing and Urban Development secretary and a rising star in the Democratic Party, was in Portland Monday morning for a private fundraiser for presidential candidate Hillary Clinton.

The event at the law offices of Preti Flaherty in downtown Portland included U.S. Rep. Chellie Pingree and longtime Maine lobbyist and attorney Tony Buxton.

According to an invitation provided by Hillary for America, Castro’s visit was billed as “coffee and conversation.” It was closed to the public and to the media.

Castro arrived at the fundraiser with Pingree and his twin brother, U.S. Rep. Joaquin Castro, D-Texas. After the event, Julian Castro said the crowd was enthusiastic and looking forward to seeing Clinton win the nomination.

When asked if he would accept if Clinton wins the nomination and asks him to run for vice president, he would say only that he is focused on his work with HUD and campaigning for Clinton.

“Both Joaquin and I are happy to help her out,” he said.

Julian Castro, the former mayor of San Antonio, was tabbed by President Obama in 2014 to serve as secretary of the Department of Housing and Urban Development. His ethnic background – Mexican American – makes him a powerful surrogate for Clinton, who will likely need strong support from Hispanic voters, both in the Democratic primaries and in the general election, if she becomes the nominee.

During an interview Monday morning on the “Ken & Mike” show on WGAN, the Castro brothers said they have long supported Clinton, whom they described as a tenacious and strong leader.

When asked by the radio hosts if he would accept an invitation to be Clinton’s running mate if she wins the nomination, Julian Castro said he feels “it’s not going to happen.”

“That’s flattering, but I doubt that,” he said. “I fully expect a year from now to be back in Texas.”