Former Wyoming Rep. Cynthia Lummis (R) on Thursday officially filed to run for outgoing Sen. Mike Enzi’s (R-Wyo.) seat in 2020.
Lummis, a former member of the conservative House Freedom Caucus, previously represented the Equality State as the state’s lone House representative, but opted not to seek reelection in 2016.
Enzi, 75, in May announced his plans to retire from the upper chamber after serving 22 years.
Lummis is likely to face a difficult primary challenge, with many speculating House Republican Conference Chairwoman Liz Cheney(Wyo.) may opt to run for the position.