US election 2016: Sanders aims for win in West Virginia
The US states of Nebraska and West Virginia hold primary votes on Tuesday, with Bernie Sanders still battling to slow Hillary Clinton's march to the Democratic nomination.
Mr Sanders is expected to perform well in West Virginia, despite Mrs Clinton's huge lead in overall delegates.
"We're going to fight for the last vote," Mr Sanders said on Monday.
Minutes after the West Virginia polls closed, Donald Trump was projected the winner in the Republican race.
And he later was declared the winner in Nebraska too, which was a Republican-only contest.
He is the party's presumptive nominee after his last remaining rivals left the race last week, although their names remained on the West Virginia ballot.
According to exit polls, the most important issue for voters in that state was the economy and jobs.
- West Virginia results as they come in
- Nebraska Republican results as they come in
- Why Bernie Sanders is still running
- Who will be Trump's running mate?
- Trump v Republicans - the gulf between
Mr Trump is now trying to unite the Republican Party after a contentious primary season.
Many top Republican leaders, including House Speaker Paul Ryan, have declined to support Mr Trump's candidacy, saying the New York businessman does not represent conservative values.
Mr Trump will meet Senate Majority Leader Mitch McConnell and Mr Ryan on Thursday in hopes of resolving their differences.
Some Republicans are concerned that Mr Trump will negatively affect other races, hurting the party's chances of retaining control of Congress.
Mr Trump is deeply unpopular among key voting blocs including women, Latinos and African Americans.
On the Democratic side, Mrs Clinton is on the defensive in West Virginia because of comments she made during a town hall meeting in March.
Addressing environmental issues, she said she wanted to put coal companies out of business.
Battered by dwindling demand and new environmental rules, coal companies are among the top employers in West Virginia.
Mrs Clinton later said she had misspoken and that she had wanted to bring new industries to the state.
Mr Sanders's message of economic fairness has also resonated in West Virginia, one of the poorest states in the country.
While a win in West Virginia will not derail Mrs Clinton's path to the Democratic nomination, Mr Sanders' continued success will give him leverage to influence the party's platform.