PORTLAND, Ore. (KOIN) — Oregon is an increasingly important state in the race for the White House and more candidates are expected to visit between now and the May 17 primary.

Most years the leading candidates have wrapped up their party’s nomination by the time Oregon’s primary rolls around. Not so in 2016.

Hillary Clinton leads Bernie Sanders on the Democratic side, but it’s still a contest. The real struggle is on the Republican side as front-runner Donald Trump likely won’t get the 1237 delegates he needs to clinch a first-ballot nomination at the GOP convention in Cleveland in July.

The head of the Oregon GOP said its possible Trump, Ted Cruz and John Kasich could all visit Oregon before the primary.

California, with its hundreds of delegates at stake, doesn’t take place until June — meaning Oregon’s primary really matters.

To vote in Oregon’s primary, a registered voter must choose a party. The deadline for doing that is April 17.