Greg Treat Republican Greg Treat Republican The 2020 Oklahoma Senate election was held as part of the biennial elections in the United States.

Those incumbents are: Four Republicans lost renomination.

A special election for Oklahoma State Senate District 28 has been called for November 3, 2020.

The candidate filing deadline was April 10, 2020.

The seat became vacant after Jason Smalley resigned his seat on January 31, 2020, to take a private-sector job with Motorola Solutions Corporation.