[3][4] Republican U.S. Representative Roger Marshall was considered a narrow favorite based on polling, but he won by around 11 points, a larger margin than most experts predicted.

In a live-streamed debate on May 22, 2020, in a ballroom devoid of spectators due to the COVID-19 pandemic, all five major candidates praised president Donald Trump.

[37] Marshall said, "We cannot afford to send a failed candidate back this fall who will lose to Barbara Bollier and hand the Senate majority over to Chuck Schumer."

Referring to Marshall, Kobach replied, "Do you want a go-along-to-get-along kind of senator, a gutless wonder who never takes a stand, or, do you want someone who poses a threat?"

[37] Objecting to the party pressure, Lindstrom characterized his opponents as "shortsighted, self-serving ... career politicians who are divisive, controversial," and, "have a record of losing elections.