CHICAGO (CBS) — Progressive challenger Marie Newman scored an upset on Tuesday in her second bid to defeat eight-term incumbent U.S. Rep. Dan Lipinski (D-Illinois) on Tuesday in the state’s 3rd Congressional District.

A member of the Lipinski family has held that seat since 1983.

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Newman declared victory late Tuesday night, holding a lead of just more than 2,100 votes, virtually the same margin by which Lipinski defeated Newman in 2018.

With more than 98% of the vote counted, Newman was leading Lipinski 47% to 44.9%. Rush Darwish, a Palestinian-American business owner, was in third place with 5.9% of the vote, and Charles Hughes, a Nicor operation mechanic and former candidate for alderman in Chicago’s 23rd Ward, was in last with 2.3% of the vote.

However, Lipinski has yet to concede, and did not show up for a scheduled media appearance late Tuesday night.

Keep track of the results here.

The 3rd District includes portions southwest of Chicago and Cook County. Some of those areas include Oak Lawn, Homer Glen, Lemont, Lockport and Stickney.

The incumbent congressman has held his seat in the 3rd District in Illinois since 2005, when he replaced his father, Bill Lipinski, who had been the 3rd District representative since 1983.

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The younger Lipinski had not faced a serious election challenge since taking office before Newman’s upstart campaign in 2018. However, some Democrats believe he is not in line with his party in Illinois and Washington, and Newman nearly rode a surge of progressive support to victory two years ago before finally pulling off a win on Tuesday.

Newman, who owns her own marketing company, has said Lipinski is too conservative, especially on issues such as abortion, health care, and immigration; and has slammed him for his votes against Obamacare, and the DREAM Act to provide a path to citizenship for some undocumented immigrants.

Earlier this year, Lipinski was under fire for signing onto amicus brief asking the U.S. Supreme Court to consider overturning Roe v. Wade.

Planned Parenthood Illinois Action denounced Lipinksi for signing onto the amicus brief.

“This case could decide the future of abortion access in this country and we will not not silently stand by and let Congressman Lipinski pledge his support for taking away Illinois woman’s right to a safe and legal abortion,” Brigid Leahy, Senior Director of Public Policy for Planned Parenthood Illinois Action, said in a news release.

Newman had the backing of many prominent progressive Democrats, including Mayor Lori Lightfoot, U.S. Senators Elizabeth Warren and Bernie Sanders, and Congresswomen Alexandria Ocasio-Cortez and Ayanna Pressley.

However, Lipinski had the support of several major labor unions, as well as many mayors in the 3rd District.

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Newman will face off against Will County board member Mike Fricilone in the general election in November. Fricilone handily defeated real estate broker Catherine O’Shea and Holocaust denier and neo-Nazi Arthur Jones in the GOP primary.