She left quickly after her speech, departing before Obama's arrival. But his supporters made their presence known, sending up chants of "Obama" from the audience as she made her way offstage.
Obama's winning margins ranged from substantial to crushing.
He won roughly two-thirds of the vote in Washington state and Nebraska, and almost 90 percent in the Virgin Islands.
Nearly complete Louisiana returns showed Obama with 57 percent of the vote, to 36 percent for the former first lady. As in his earlier Southern triumphs in Alabama, Georgia and South Carolina, Obama, a black man, rode a wave of African-American support to victory in Louisiana. Clinton won the white vote overwhelmingly.
In all, the Democrats scrapped for 161 delegates in the night's contests.
In incomplete allocations, Obama won 72, Clinton 40.
In overall totals in The Associated Press count, Clinton had 1,095 delegates to 1,070 for Obama, counting so-called superdelegates. They are party leaders not chosen at primaries or caucuses, free to change their minds. A total of 2,025 delegates is required to win the nomination at the national convention in Denver.
McCain flunked his first ballot tests since becoming the Republican nominee-in-waiting. He lost Kansas caucuses to Mike Huckabee, gaining less than 24 percent of the vote. Huckabee, the former Arkansas governor, got nearly 60 percent of the vote a few hours after saying, "I majored in miracles, and I still believe in them." He won all 36 delegates at stake.