TOPEKA, Kan. (AP) —Former Kansas Secretary of State Kris Kobach is launching a campaign to run for the U.S. Senate next year.

Kobach filed paperwork Monday with the Federal Election Commission forming a campaign committee. He scheduled a speech Monday afternoon in Leavenworth.

He is seeking the Republican nomination for four-term GOP Sen. Pat Roberts’ seat. Roberts is not seeking re-election in 2020.

Some Republicans do not want Kobach to run for the Senate because he lost the governor’s race last year to Democrat Laura Kelly.

Kobach is an advocate for tough immigration policies. He was an early and vocal supporter of President Donald Trump in 2016 but has frequently alienated GOP moderates.

Kobach is joining a potentially crowded race. At least 16 prospective candidates have expressed an interest in running.

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