The upcoming May primary election will be Idaho's first under the state's new closed-primary and party registration law, and the new rules are causing lots of confusion. Idaho Statesman reporter Cynthia Sewell has a nice how-to article about it here. The upshot: To vote in the primary, you have to register your affiliation with a party – Constitution, Democratic, Libertarian or Republican – or choose unaffiliated. Only those who register as Republicans can vote in the GOP primary. Anyone can vote in the Democratic primary – except those who vote in the Republican primary, because you can only vote in one or the other - and anyone can vote on the nonpartisan offices, which in May are just unopposed judicial races. Whatever choices you make, they'll be public record.