Roger Wayne Marshall (born August 9, 1960) is an American politician, physician, and former military officer serving as the junior United States senator from Kansas since 2021.

An obstetrician, Marshall was first elected to Congress in 2016, defeating incumbent Tim Huelskamp in the Republican primary for Kansas's 1st congressional district.

[2][3][4] Marshall serves on the Senate Agriculture, Nutrition, & Forestry; Finance; Budget; and Health, Education, Labor, & Pensions Committees.

[10] Marshall has served as chairman of the board of Great Bend Regional Hospital and vice president of the Farmers Bank and Trust, and has been a district governor of Rotary International.

[13] Marshall ran against incumbent Tim Huelskamp in the Republican Party primary election for Kansas's 1st congressional district in the United States House of Representatives.

[16] In the general election, Marshall won handily, defeating independent candidate Alan LaPolice and Libertarian Kerry Burt with 65.9% of the vote.

[16][17] Marshall represented a district that had long been nicknamed "the Big First" because it covered all or part of 63 counties in central and western Kansas, more than half the state's land mass.

The Republican and Democratic committee members were meeting in a Sensitive Compartmented Information Facility (SCIF) to hear testimony from Deputy Assistant Secretary of Defense Laura Cooper in connection with the impeachment inquiry against Donald Trump.

[22] In the Republican primary election, Marshall faced Kris Kobach, a polarizing ex-Kansas Secretary of State and Donald Trump ally[23] known for his far-right views.

[23] The rival campaigns and outside groups (super PACs) spent millions in attack ads; the primary was anticipated to be close, but Marshall ultimately won by 14.2 percentage points with 40.3% of the vote, although the second-place finisher (Kobach) and third-place finisher (Kansas City based plumber Bob Hamilton) combined for a higher total.

[25] In the general election, Marshall defeated Democratic State Senator Barbara Bollier 53% to 42%, with the Libertarian Jason Buckley receiving 5%.

[27] In so doing, he continued a long line of former congressmen from the "Big First" subsequently representing Kansas in the Senate; due to its vast size, the district's congressman is usually reckoned as a statewide political figure.

[31] In December 2020, Marshall was one of 126 House Republicans to sign an amicus brief in support of Texas v. Pennsylvania, a lawsuit filed at the United States Supreme Court contesting the results of the 2020 presidential election, in which Joe Biden defeated[34] Trump.

The Supreme Court declined to hear the case on the basis that Texas lacked standing under Article III of the Constitution to challenge the results of an election held by another state.

"[40] Marshall was participating in the certification of the Electoral College count when Trump supporters stormed the United States Capitol.

He blamed "the rioters, vandals, and trespassers" for destroying "any chance we had for peaceful discussion and debate on restoring and ensuring confidence in this and all future elections."

[41] As a result of his refusal to certify the count, the Kansas Democratic Party called for his expulsion from Congress for failure to "execute [his] oath of office to support and defend the United States Constitution".

[43] The McPherson Sentinel editorial board wrote that Marshall "should be ashamed" of his decision to support false claims of voter fraud and trying to overturn the election.

"[46] During the COVID-19 pandemic, Marshall has promoted conspiracy theories that falsely suggest that the Centers for Disease Control and Prevention were inflating coronavirus death numbers.

[68] Marshall supported Trump's Executive Order 13769, which barred citizens of seven Muslim-majority nations from entering the United States.