Republican state Sen. Barb Kirkmeyer filed paperwork Monday to run to be Colorado’s next governor, making the Brighton lawmaker’s long-anticipated campaign official.

Kirkmeyer, who lost a close race for Congress in 2022, plans to make a formal announcement Tuesday evening in Fort Lupton, her campaign said in a release.

The 66-year-old dairy farmer and fourth-generation Coloradan joins a crowded field of Republicans hoping to take over after next year’s election from term-limited Democratic Gov. Jared Polis in a state that has only elected one Republican governor in the last 50 years.

Including Kirkmeyer, 16 Republican candidates have launched candidacies for governor, including former U.S. Rep. Greg Lopez, a former Parker mayor making his third run for the office; state Sen. Mark Baisley, R-Woodland Park; state Rep. Scott Bottoms, R-Colorado Springs; Teller County Sheriff Jason Mikesell; and former congressional hopeful Joshua Griffin.

The Democratic primary is shaping up to be a two-way race between three-term U.S. Sen. Michael Bennet and Attorney General Phil Weiser, who is term-limited in his current position.

Polis, a wealthy former five-term congressman from Boulder, won reelection to a second term in 2022 by a nearly 20-point margin over Republican nominee Heidi Ganahl, a former University of Colorado regent.

If elected, Kirkmeyer would be the first woman to serve as governor of Colorado in the state’s 150-year history.

A member of the powerful Joint Budget Committee, Kirkmeyer is in the middle of her second term representing Senate District 23, which covers parts of Weld and Larimer counties. Before her election to the legislature, Kirkmeyer served nearly two decades as a Weld County commissioner in non-consecutive terms, starting in 1993, and ran the Department of Local Affairs under Republican Gov. Bill Owens.

While on the county commission, Kirkmeyer backed an unsuccessful 2013 bid by Weld County and 12 other neighboring rural counties to secede from Colorado to form a new state. The next year, she mounted a brief campaign in the 4th Congressional District but didn’t make the primary ballot.

In 2022, however, Kirkmeyer won the GOP nomination in the newly created 8th Congressional District in a bruising, four-way primary. She went on to lose the general election by a narrow margin to Democrat Yadira Caraveo in one of the closest congressional races in the country that cycle.

National election analysts list next year’s Colorado gubernatorial race as solidly in the Democrats’ column, citing the party’s record of sweeping every statewide election since 2018.