A political newcomer, who in June beat Donald Trump's nominee in a Republican primary, is now set to become the youngest Congressman since 1965.
Madison Cawthorn comprehensively defeated his Democratic rival in North Carolina's 11th Congressional District, securing about 54% of the vote.
The motivational speaker and real estate investor only turned 25 - the minimum age for Congress - in August.
But the lawmaker, who is a wheelchair user, has already courted controversy.
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Mr Cawthorn is potentially the third-youngest person in US history to be elected to Congress. He is a few months behind Jed Johnson Jr, a representative for Tennessee, who took office in 1965 seven days after his 25th birthday.
The youngest House member is believed to be William Charles Cole Claiborne, another Tennessee lawmaker. He was elected in 1797 on a Democratic-Republican party ticket, according to US House records, and would have been aged either 21 or 22. However, his gravestone says he was 23, while other sources indicate he was 24.
He served in Congress despite not meeting the constitutional age requirement.
Mr Cawthorn is now seen as a rising star in the Republican party after beating Trump's nominee Lynda Bennett in June's Republican Congressional primary in North Carolina.
During his primary campaign, Mr Cawthorn, who is partially paralysed after a car accident in 2014, criticised his opponent for refusing to take part in debates, saying in one video that he would not "cower behind big-name endorsements".
Despite this, he has repeatedly stated his support for President Trump.
In the Congressional race, Mr Cawthorn defeated Democratic candidate Moe Davis, a former Air Force prosecutor, near-complete results show.
Mr Cawthorn says he has decided to go into politics to combat Democratic House Speaker Nancy Pelosi and Alexandria Ocasio-Cortez, who until now was the youngest serving member of Congress. She was elected in 2018, aged 29.
Mr Cawthorn says that "our faith, our freedoms and our values are under assault from coastal elites and leftists like Nancy Pelosi and Alexandria Ocasio-Cortez".
"I'm a proven fighter - overcoming life's toughest challenges. Now I'm ready to take on the liberals in Congress," he wrote on his website., external
He describes himself as a "constitutional conservative", saying he wants to "apply timeless American principles like freedom, liberty, equality and opportunity to today's challenges".
Mr Cawthorn worked as a staff assistant for Republican congressman Mark Meadows, who is chief of staff to President Donald Trump.
He also studied political science at Patrick Henry College, an evangelical Christian school in Virginia, but dropped out after one semester. In a 2017 deposition, published by news outlet AVL Watchdog, he said his injuries had affected his ability to learn.
Mr Cawthorn is the sole owner and employee of an investment company called SPQR LLC, which has reported no income, according to a financial disclosure form he signed before running for Congress.
In 2017, Mr Cawthorn was criticised for comments he made after visiting Hitler's Eagle's Nest vacation house in Germany.
On his Instagram page, Mr Cawthorn wrote: , external"The vacation house of the Führer. Seeing the Eagles Nest has been on my bucket list for awhile, it did not disappoint.
"Strange to hear so many laughs and share such a good time with my brother where only 79 years ago a supreme evil shared laughs and good times with his compatriots."
Mr Cawthorn's opponents immediately seized on his remarks, with some suggesting he was a white supremacist.
He has repeatedly dismissed the allegations. In an August post on his Facebook page, he wrote:, external "When I visited the Eagle's Nest this was the history I had in mind. It was a surreal experience to be remembering their joy in a place where the Nazi regime had plotted unspeakable acts of evil."
Critics have also accused Mr Cawthorn of creating a misleading impression that he was due to attend the US Naval Academy before his car accident - an image that has been central to his campaign.
On his website, Mr Cawthorn said he was nominated to the Academy but "[his] plans were derailed" after the car accident. But in a 2017 deposition, he admitted that his application had been rejected before the crash.
Earlier this year, several women accused Mr Cawthorn of sexual misconduct during his student years.
He denies the allegations.