WRAPUP 10-Edwards backs Obama's White House bid

* Obama gets major endorsement from Edwards

* Clinton says race is not over yet

* Obama looks ahead to McCain

* Five nominating contests remain (Adds quotes, details; paragraph 8)

By Jeff Mason

GRAND RAPIDS, Mich., May 14 (Reuters) - Former U.S. presidential candidate John Edwards endorsed Democrat Barack Obama on Wednesday, giving a major boost to the Illinois senator's efforts to unify the party behind his bid for the White House.

Edwards, the 2004 vice presidential nominee, had been heavily courted by both Obama and rival Hillary Clinton in the past few months.

"The reason I am here tonight is the Democratic voters in America have made their choice and so have I," Edwards, who dropped out of this year's Democratic race in January, said at a rally with Obama in Grand Rapids, Michigan.

"There is one man who knows in his heart that it is time to create one America, not two, and that man is Barack Obama," he said, as Obama sat on a stool behind him.