Unaffiliated voters can now participate in the June 26 primary election, which will choose which Republican and Democratic candidates move forward to the general election in November. That's thanks to the passing of Proposition 108 in 2016.

But there's one crucial point to remember: Unaffiliated voters may only participate in one primary, meaning they cannot vote in both parties' races. The Colorado Secretary of State's Office reminds voters to return only the Republican or the Democratic ballot — if they return both, neither will count.

Voting with the ballot of a political party does not affiliate a voter with either party, according to the office.

Ballots were to be mailed beginning June 4 to active registered voters. Arapahoe County must receive ballots by 7 p.m. June 26 to be counted, according to the county clerk and recorder's office. Postmarks do not count as received. It recommends returning the mail ballots by June 19 to ensure they arrive on time. Voters can also go to a ballot drop-off box — visit arapahoevotes.com/ballot-drop-off-locations to find locations. Those are open until 7 p.m. June 26.

From June 18-26, voters can visit a voter service and polling center, where they can register to vote in person, update voter registration, drop off or request a ballot, replace a damaged ballot, or vote on an electronic tablet.

For the list of locations, which include Aurora, Centennial and Littleton, visit arapahoevotes.com/voter-service-polling-centers.

The primary election includes candidates for the United States House of Representatives; state races, including governor, attorney general, the state House and board of education; and county races, such as assessor, sheriff and county commissioner.

Unaffiliated voters make up the largest group of registered voters in Arapahoe County, with about 162,700 registered. Democrats measure in at about 138,900, and about 113,800 are Republicans, according to the county clerk and recorder's office's website.

Voters affiliated with a minor political party — such as the American Constitution, Green or Libertarian parties — will not receive a mail ballot unless their party holds a primary election, according to the Secretary of State's Office. About 7,200 voters are registered to minor parties, according to the clerk and recorder's office.

If unsure of their voter registration or affiliation, voters can check their information at sos.state.co.us/pubs/elections/chooseU/choiceHappens.html.

For other questions, contact the clerk and recorder's office at 303-795-4511 or elections@arapahoegov.com.