Democrats Flipped One US Senate Seat Fairly Early Tuesday Night

Democrats flipped one U.S. Senate seat fairly early Tuesday night.

Current U.S. Rep. Tammy Duckworth of Illinois ousted Republican Sen. Mark Kirk.

Kirk, who represents a traditionally blue state, was viewed as possibly the most vulnerable Republican senator facing re-election.

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He didn't help himself during a recent debate.

"My family has served this nation in uniform going back to the Revolution. I'm a daughter of the American Revolution," Rep. Tammy Duckworth said during the debate late last month. 

Kirk responded, "I'd forgotten that your parents came all the way from Thailand to serve George Washington."

Rep. Tammy Duckworth's mother is an immigrant, but her father's family has traced its roots in service back to the American Revolution, as she later pointed out on Twitter.

Duckworth is an Iraq War veteran who was awarded a Purple Heart after losing both her legs when her helicopter went down.

She'll join fellow Democrat, Sen. Dick Durbin, in representing Illinois.