Marjorie Taylor Greene, a businesswoman who has expressed racist views in videos shared online, beat neurosurgeon, John Cowan, in the 14th congressional district race, securing 57 per cent of the vote.
Addressing her supporters in a victory speech, later posted on social media, Ms Green criticised the Democrat House speaker Ms Pelosi, whom she also labelled “anti-America”.
“I just wanna say to Nancy Pelosi. She’s a hypocrite,” Ms Greene can be heard saying in the video. “She’s anti-American. And we’re going to kick that b***h out of Congress,” she added to loud applause.
Georgia’s 14th congressional district is heavily conservative and has not elected a Democrat since its creation in 2013, meaning Ms Greene has essentially secured guaranteed a seat in Congress.
“So the Republican establishment was against me. The DC swamp has been against me. And the lying fake news media hates my guts,” Ms Green said in her victory speech. “Yep, it’s a badge of honour.”
She has amassed tens of thousands of followers on social media, where she often posts videos of herself speaking directly to the camera. Those videos have helped propel her popularity with her base, while also drawing strong condemnation from some future would-be colleagues in Congress.
In a series of videos unearthed just after Greene placed first in the initial 9 June Republican primary, she complains of an “Islamic invasion” into government offices, claims Black and Hispanic men are held back by “gangs and dealing drugs,” and pushes an anti-Semitic conspiracy theory that billionaire philanthropist George Soros, who is Jewish, collaborated with the Nazis.
Several high-profile Republicans then spoke out against her. House minority whip Steve Scalise of Louisiana quickly threw his support behind Cowan, while Rep. Jody Hice of Georgia rescinded an endorsement of Ms Greene.
Ms Greene also is part of a growing list of candidates who have expressed support for QAnon, the far-right U.S. conspiracy theory popular among some supporters of President Donald Trump. Lauren Boebert, another candidate who has expressed support for QAnon, recently upset a five-term congressman in a Republican primary in Colorado.
Ms Greene has positioned herself as a staunch Trump supporter and emphasises a strongly pro-gun, pro-border wall and anti-abortion message. She has also connected with voters through an intensive effort to travel the district and meet people on the ground.
Larry Silker, a 72-year-old retiree, cast a ballot for Ms Greene last week at an early voting location in Dallas, Georgia.
“She seems to be a go-getter, you know. She’s out seeing everybody that she can, and I think that’s nice,” Mr Silker said.
Asked whether he had seen criticism of Greene’s remarks, Mr Silker said: “Well yeah, you know, you see it. But do you put faith in it? You just have to weigh it out.”
Voter Pamela Reardon said she supports Greene because she connects with people, and she’s anti-abortion, a defender of the Second Amendment and “a true Christian.”
“I got behind her because of her honesty,” she said. “She’s not going to be bought by anybody. I could tell that her heart was pure.”
Ms Reardon is familiar with criticism of Ms Greene’s social media posts and videos but says “she’s never said anything racist like they say she has,” and blamed attacks by her opponent’s campaign.
The district stretches from the outskirts of metro Atlanta to the largely rural northwest corner of the state.
Ms Greene will face Democrat Kevin Van Ausdal in November. Van Ausdal acknowledged that he faces an uphill battle in the heavily conservative district in an interview Tuesday night and called on people across the country to rally behind his campaign.
“Honestly the local Democratic money is not a lot,” he said.
“We need donors to help get out the message and show people that there is an alternative, and a great alternative, to QAnon conspiracies and divisive rhetoric,” he said.
Republican Rep. Tom Graves, who did not seek reelection, last won the seat with over 76% of the vote in 2018.
Additional reporting by Associated Press