Democratic presidential candidate Bill Richardson dropped his bid for the party's nomination on Thursday, leaving only three major players in the battlefield.

"It is with great pride, understanding and acceptance that I am ending my campaign for president of the United States," he told supporters in Santa Fe, New Mexico.

"It's been an exhilarating and humbling year. An experience I will treasure and I will never forget."

The 60 year-old New Mexico governor who was vying to become the first Hispanic U.S. president, won only 5 percent of the Democratic votes in the New Hampshire primary on Jan. 8 and 2 percent in the Iowa caucuses.

Richardson refused to endorse any one of the three candidates left in the campaign -- Barack Obama, Hillary Rodham Clinton and John Edwards, who are fighting to clear their paths to the nomination and then the White House.

"At this time I will not endorse any candidate," the governor said. "And all I ask of the candidates is that they do not resort to personal attacks to win the nomination. Our country and our party deserve better than that."

Richardson, who was born by a Mexican mother, grew up in Mexico City but received his high school and college education in the United States.

He was elected to a second term as New Mexico governor in 2006. Prior to that, he served from 1982-1997 in the House of Representatives, U.S. Ambassador to the United Nations and Energy Secretary in President Bill Clinton's administration

Although losing his presidential bid, Richardson was mentioned as a vice president candidate or state secretary potential if Democrats win over the White House.

(Xinhua News Agency January 11, 2008)