Scyller Borglum

Scyller J. Borglum (born June 19, 1977) is an American politician and engineer from the state of South Dakota. A Republican, Borglum served in the South Dakota House of Representatives for the 32nd district from 2018 to 2021.

Borglum unsuccessfully ran to represent South Dakota in U.S. Senate in 2020, losing the Republican primary to incumbent Mike Rounds. Borglum attended Pacific Lutheran University, where she earned a Bachelor of Business Administration. She received a Fulbright Scholarship, which she used to study oil and gas development in Oslo, Norway.

After her brother, Troy, died in a traffic collision, Borglum went to Duke Divinity School, and earned a master's degree in theological studies (MTS) in 2003. She then worked in pharmaceutical sales in Oregon and Texas. Governor Dennis Daugaard appointed Borglum to fill McPherson's vacant seat on August 8. She was elected to a full term in November.

Borglum ran in the Republican primary for the United States Senate against incumbent Mike Rounds in the 2020 election. She positioned herself as an ally of then-President Donald Trump. She accused U.S. Representative Dusty Johnson of having worked to intimidate her on Rounds' behalf to keep her out of the Senate race. Rounds defeated Borglum, 75% to 25%.

Post-political career Borglum recently was hired by Westlake Petrochemical as a Salt/Brine expert as of September 2025. Borglum was vice president for underground storage at WSP Global, an engineering firm through 2025 In 2024, Borglum authored the book STEM Study Habits: Successfully Navigate Math, Science, Engineering, and Life for Your Degree.

Personal life Borglum married Timothy Masterlark, a professor at the South Dakota School of Mines and Technology, in 2018.