Things were going so well for Democratic Sen. Mark Udall of Colorado.

Sure, he sits in a swing state, and recent polls show that he is hurting from the national troubles of Obamacare.

But Republicans — stop me if you’ve heard this one — couldn’t seem to get their act together for this year’s midterm election. The GOP looked ready to nominate District Attorney Ken Buck, the same Ken Buck who lost what looked like a lay-up race against freshman Democratic Sen. Michael Bennet in 2010.

Then, in a turn of events that would make the “House of Cards” writers blush, this past week Rep. Cory Gardner, a rising Republican star who had previously spurned a challenge to Udall, decided to run. Buck quickly dropped out of the race to run for Gardner’s now-open 4th Congressional District seat. State Rep. Amy Stephens also abandoned her Senate candidacy, calling Gardner “the great uniter .”

And voila! Within 48 hours, Udall went from being a safe incumbent to being one of the half-dozen or so most endangered senators on the ballot this fall.

Sen. Mark Udall (D-Colo.) in 2012. He’s gone from having a lackluster opponent to a formidable one. (Alex Wong/Getty Images)

Udall has plenty of strengths, with or without Gardner in the race. Chief among them is the $5 million in his campaign account. And while Gardner is a significant improvement from the D-list candidates Republicans had earlier, he is still a member of a decidedly unpopular congressional GOP.

A week ago, Udall was plotting committee assignments in the 114th Congress. Today he is bracing for a real fight for a second term.

Mark Udall, for watching your opponent turn from a frog to a prince, you had the worst week in Washington. Congrats, or something.

Have a candidate for the Worst Week in Washington? E-mail Chris Cillizza at

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