Colorado's most endangered Democratic member of Congress, Rep. Betsy Markey, has lost her seat. Republican challenger, Cory Gardner, won the race, 52 percent to 43 percent.Cory GardnerBetsy MarkeyDoug AdenKen WaszkiewiczDuring his acceptance speech on Tuesday night, Gardner said, "This is not a victory for one campaign, this is a victory for all of us."He said both parties had failed the American people and he wanted to go to Congress to create jobs. He said he wanted to send the country and the rest of the world a message: "America, we're back."Gardner criticized Markey and ruling Democrats for spending too much. He believed that the health care overhaul was too expensive and should be repealed. He also supportted a constitutional amendment requiring a balanced budget."The sun will come up tomorrow. We're all going back to work. Keep believing and know that it has been my honor to serve as your Congresswoman for the 4th Congressional district these past two years," Markey said during her concession speech.Markey tried to tout her independent streak in the Republican-leaning district, saying she voted against President Barack Obama's first budget and against the health care overhaul the first time it was before the House. But Markey was a crucial vote for the Democrats last year on the final version of the health care overhaul.When Markey was elected to the sprawling northern and eastern Colorado district two years ago, she was the first Democrat elected to the seat in more than three decades. She's always been considered a vulnerable incumbent because Republicans outnumber Democrats in her district.More than $5 million was spent on the race.