MISSOULA, Mont. - In Missoula County, GOP voters may have a tough choice to make in the primary election.
Montana has an open primary -- a registered voter doesn't need to be a member of the party to vote. But voters have to choose one ballot, Democrat or Republican.
"A Republican voter will probably have to decide what races are more important to them," said Missoula County Clerk and Recorder/Treasurer Vickie Zeier.
In the races for Missoula County sheriff and Missoula county attorney all of the candidates are Democrats. So, if a voter chooses to weigh in on those races they have to pick Democrat candidates in the U.S. House and Senate races.
But if a voter chooses to vote on the Republican ballot for the U.S. races, they don't get to help decide the local races.
Montana Republican Party Chair Will Deschamps is asking Republican voters to side with their party.
"Well, obviously I'm suggesting that they all go out and vote, number one. Number two, that they vote on a Republican ballot."
He said local offices like sheriff and county attorney shouldn't be divided by party lines in the first place.
"The county attorney is in charge of processing criminals or deciding the criminality of a person," Deschamps said. "The sheriff's office is in charge of over watching the public and making sure they're safe. So those are seen in my opinion as nonpartisan efforts."
But Zeier said there will likely be some crossover voting.
"A Republican will vote a Democrat ballot or a Democrat will vote a Republican ballot," she said. "These are two very popular races -- the sheriff and the county attorney's race -- so I do expect to see quite a bit of crossover voting."
At the end of the day, it's up to voters. For Republicans, Deschamps' message is clear: "If we start crossing over, we lose those votes on the Republican side of the primary."
Ballots will be mailed out May 5. Election day is June 3.
Montana is one of 13 states with an open primary where registered voters can vote for one party or the other.
Idaho had its first closed primary in 2012. Only voters who are registered with a party can vote.
Washington state and two others have what's called a blanket primary, where all candidates are on one ballot and the top two move on to the general election.