Joe Biden has won Idaho's Democratic presidential primary. The state has 20 pledged delegates at stake.
Democrats in Idaho are using a primary for the first time. They used a caucus in 2016 to pick Bernie Sanders over Hillary Clinton for the Democratic presidential nominee.
Officials have said switching to a Democratic primary this year from a caucus could significantly increase the number of participants and play a role in the outcome.
President Donald Trump is expected to have little difficulty winning the state in the November general election.
Idaho last year was the nation's fastest-growing state, with close to 37,000 new residents boosting its population to nearly 1.8 million. That's a 2.1% population increase.
Biden also won primaries Tuesday in Michigan, Missouri and Minnesota.