That is in addition to the regular Idaho Primary Election set for May 19, when voters will choose party nominees for the Idaho Legislature, county offices, both U.S. House seats, and the U.S. Senate seat currently held by Sen. Jim Risch (R-Idaho).
To vote in the Republican presidential primary in March or the regular Republican primary in May, you must declare affiliation with the Republican Party.
Unaffiliated voters are allowed to vote in the Democratic and Constitution party primaries, but not the Republican primary.
March 13 is the deadline to change your party affiliation or switch to "unaffiliated" for the May 19 non-presidential primary.
The Idaho Secretary of State has posted online information about the parties' participation as well as a list of the candidates in the presidential primaries.
In-person early voting for the presidential primaries runs February 24 through March 6 in the counties that offer it.
Canyon County offers early voting at just one location, the elections office at 1102 E. Chicago in Caldwell.
Ada County's early-voting locations include the elections office at 400 N. Benjamin Lane; Boise City Hall at 150 S. Capitol Blvd.; and Meridian City Hall. A mobile voting center will also be at several locations around the county.
In addition to voting for presidential candidates on March 10, some voters will be asked to approve funding for local school districts. You can find a county-by-county breakdown of all school funding requests here.
More voter resources are available on the Idaho Votes page.
The Idaho Democratic Party held county caucuses rather than a primary in 2016. Thousands attended the Ada County caucus at CenturyLink Arena and the Boise Centre. That was believed to be one of the largest single-site caucuses in the nation, but was also marked by long lines and a process that took several hours. The party announced in 2018 that it would switch from using caucuses to a state-run primary for 2020.
Idaho Democrats will still hold County Delegate Selection Caucuses, where on April 4 counties will select delegates to the Democratic state convention. Delegates to the national convention will be selected at the state convention, which will take place in June.
The Idaho Republican Party held presidential caucuses in 2012, but switched to a presidential primary in 2016.
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