Sen. Joni Ernst, R-Iowa, plans to announce that she will not run for re-election next year, according to a person familiar with her decision.

The move would open up another potentially competitive race in Iowa, months after GOP Gov. Kim Reynolds announced she wouldn’t run for re-election either. But while Democrats have been eyeing underdog bids in both races, they’ve struggled in recent statewide elections and haven’t won a Senate race in the state since 2008.