According to oklahomaconstitution.com …

The first contest in this election cycle will be the Primary which is the last Tuesday in June, which is June 28 this year.

Early voting will be June 23-25.

The deadline to register to vote in time to participate in the Primary is June 3. The Primary Election will include those races where there are two or more candidates of the same political party running for the same office.

In addition to Republican and Democrat Primary Elections, the Libertarian Party is again an officially recognized party and will have a Primary Election for some offices.

Republicans have a closed primary, where only Republicans can vote to select the nominee of their party for an office.

Both the Democrats and Libertarians have decided to allow those registered as Independent, which means not a member of a recognized party, to participate in their Primary Elections.

For those seats in which no candidate receives more than 50 percent of the vote, the Runoff Primary Election will be held on the last Tuesday of August. The date for 2016 will be August 23.

The General Election will be November 8.