TOPEKA, Kan. (AP) — Kansas Senate President Susan Wagle has launched a campaign for the U.S. Senate. The Wichita Republican and 65-year-old lawmaker filed paperwork Tuesday evening with the Federal Election Commission forming a campaign committee.

She is seeking the GOP nomination for the seat held by four-term GOP U.S. Sen. Pat Roberts. He is not seeking re-election in 2020.

Wagle has served in the Legislature since 1991 and has been the Kansas Senate’s top leader since 2013. She’s emerged as a vocal opponent of new Democratic Gov. Laura Kelly and helped thwart Kelly’s push for Medicaid expansion.

Wagle launched her campaign the same month as former Kansas Secretary of State Kris Kobach. The race already is crowded, with as many as 19 candidates considering it. Wagle is the only GOP woman running.