Richardson to endorse Obama's White House bid: source

PORTLAND, Oregon (Reuters) - New Mexico Gov. Bill Richardson endorsed Barack Obama's bid for the Democratic nomination for president, Obama's aides said on Friday, in a boost for the Illinois senator.

"I can confirm that he (Bill Richardson) is endorsing (Obama) and that he will be at the rally in Portland tomorrow," said an official with the Obama campaign.

Richardson's endorsement has been fiercely sought by both Obama and his rival Sen. Hillary Clinton in part because as a Hispanic he is seen as influential within the Latino community, which could be a key voting bloc in the November presidential election.

Hispanics, the fastest-growing segment of the electorate, largely backed Clinton in nominating contests on "Super Tuesday," with exit polls showing her winning two-thirds of the Latino vote in several states.

Obama and Clinton, a senator from New York and former first lady, are locked in a tight race for the Democratic presidential nomination to take on presumptive Republican nominee John McCain.

They have both sought high-profile endorsements as a way to bolster their campaigns. Both have also actively courted former presidential candidate John Edwards, a former North Carolina senator. Edwards has yet to endorse either candidate.

Richardson, 60, was energy secretary and U.S. ambassador to the United Nations under President Bill Clinton and served in the U.S. House of Representatives from 1982-1997.

Richardson also ran for the Democratic nomination but abandoned his bid in January, stating he lacked the funds to continue after finishing fourth in voting in Iowa and New Hampshire.

A skilled negotiator and diplomat, the popular governor has been mentioned as a possible vice presidential candidate or secretary of state in a Democratic administration. He also is a super-delegate who would have a vote in the nominating contest if neither Obama nor Clinton win enough delegates during the primaries.

Obama is due to hold a rally in Portland, Oregon, on Friday at 9:35 a.m. local time, his campaign said. He will then spend the rest of the day campaigning in the state, which holds a primary on May 20.

In a statement provided by the Obama campaign, Richardson said, "I believe he is the kind of once-in-a-lifetime leader that can bring our nation together and restore America's moral leadership in the world," according to the New York Times.

"As a presidential candidate, I know full well Sen. Obama's unique moral ability to inspire the American people to confront our urgent challenges at home and abroad in a spirit of bipartisanship and reconciliation," the Times quoted Richardson's statement as saying.

(Editing by Stacey Joyce and Vicki Allen)