Democratic challenger Tammy Duckworth has unseated Republican incumbent Mark Kirk from the U.S. Senate seat in Illinois once held by President Barack Obama.

Throughout the election season, Kirk’s seat has been viewed nationally as one of the most vulnerable seats as Republicans fought to maintain majority control of the Senate.

In an attempt to distance himself from the Republican nominee Donald Trump in Illinois, a Democratic stronghold, Kirk was the first Republican lawmaker to announce he would not support the candidate in the wake of controversial comments about Judge Gonzalo Curiel back in June.

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Duckworth told NewsChannel 5 that while serving the Senate, she will invest in quality public education, fight for fairer trade policies, and support initiatives that will bolster the middle class.

“My goal is to look out and work for Illinois families like mine, who may have been knocked down, but haven’t given up,” she said.

Duckworth, a veteran of the U.S. Army, was awarded a Purple Heart after she lost both of her legs in 2004 when a rocket-propelled grenade hit her UH-60 Black Hawk helicopter. Since then, she has made serving as an advocate for veterans one of her top priorities.

Duckworth and her family live in suburban Chicago.

Video: Mark Kirk concession speech