Sen. Hillary Clinton (D-N.Y.) asked the Sheet Metal Workers to work to get Barack Obama elected president.

The Sheet Metal Workers union has officially switched its allegiance from Hillary Clinton to Barack Obama in the race to be the Democratic presidential nominee.

The announcement came Friday as the union wrapped up its annual business conference at Walt Disney World, near Orlando, Fla.

Clinton, a Democratic senator from New York state, was there to thank the Sheet Metal Workers for its longtime support and ask members to transfer that enthusiasm to Obama. The union was one of Clinton’s earliest supporters in her presidential bid.

Obama, an Illinois senator, is expected to be officially named the Democratic presidential candidate this week at the political party’s national convention in Denver.

Sheet Metal Workers General President Michael J. Sullivan said Clinton has been a steadfast ally to America’s unions.

“She has never let her friends and supporters in the labor movement down,” Sullivan said. “There is no question in our minds -- she is and will forever be remembered as one of the most prominent leaders of the 21st century.”

He presented Clinton with an honorary Sheet Metal Workers membership card  and a small metal palm tree made by the union’s workers.

Clinton asked the 1,000 sheet metal workers in attendance to  “bring the same passion and determination that you brought to my campaign to Senator Obama’s campaign.”

Sullivan said the group would.

“The men and women of the SMWIA (Sheet Metal Workers union), who go to work every day building America, have chosen to support a candidate who will stand up for working families. Senator Obama is that candidate,” Sullivan said. “He will fight for good jobs and a stronger economy, he will fight to improve our nation’s infrastructure, stop intimidation at the workplace and bring the change working Americans need with health care reform and true retirement security.”