John Cornyn seemed to have his drive for a Republican Senate majority after the 2012 election in cruise control.

As head of the National Republican Senatorial Committee — one of the party’s top campaign arms — the Texas senator oversaw a six-seat pickup in the 2010 elections and entered this campaign season with 23 Democrats up for reelection, as opposed to just 10 Republicans.

In short: Everything was coming up Cornyn.

Until this past week, that is, when Sen. Olympia J. Snowe (R-Maine) shocked the political world by forgoing a bid for a fourth term and former senator Bob Kerrey (Neb.), the only Democrat with a fighting chance of winning in the ruby-red Cornhusker State, reversed course and decided he will run after all.

Snowe’s decision is the more important — and troublesome — for Cornyn. Had she decided to run again, she would have been a shoo-in for reelection; she is the most popular elected official in the state. Without her in the race, Democrats — and there will be any number of candidates — start with a clear edge in a state that President Obama should carry easily in November. (Obama won Maine with 58 percent of the vote in 2008.)

Rubbing more salt into Cornyn’s wound, Snowe informed him of her decision just hours before announcing it publicly. The only thing worse than a retirement in a swing seat is an unexpected one.

Kerrey, who spent two terms in the Senate in the 1990s, was recruited heavily by national Democrats after Sen. Ben Nelson (D) announced late last year that he wouldn’t be seeking a third term. Back then, Kerrey said no. But this past week he announced that he will, in fact, seek the seat he gave up more than a decade ago. Republicans are still favored in Nebraska, but Kerrey makes the race far more competitive than it would have been.

Neither Snowe’s retirement nor Kerrey’s reconsideration is Cornyn’s fault. But each creates a problem that he is responsible for solving.

John Cornyn, for watching your easy ride hit some turbulence, 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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