Bernie Sanders has won the West Virginia primary in the Democratic race for the presidential nomination, US media project.
The Vermont senator still trails Hillary Clinton in the overall contest for delegates but this win keeps his slim hopes alive.
“We are going to fight for every last vote,” he said in a victory speech that also attacked Republican Donald Trump.
Mr Trump was declared the winner in West Virginia and in Nebraska.
His last remaining rivals dropped out last week but remained on the ballot.
But Mr Trump faces a huge task in trying to get the Republican party behind him, as doubts persist about his substance and style.
House Speaker Paul Ryan, the party’s highest-ranking elected official, has said he is unable to endorse the New York businessman because he lacks conservative principles.