Republican Thad Cochran, who has represented Mississippi in the Senate since 1978, is suddenly an underdog. (Joe Ellis/Associated Press)

This can’t be how Thad Cochran imagined spending his twilight political years.

On Tuesday, Cochran, who has represented Mississippi in the Senate since 1978, found himself on the wrong end of a Republican Senate primary vote. It was Chris McDaniel, a conservative state senator, who led the field, followed — 1,386 votes behind — by Cochran.

The good news for the incumbent was that McDaniel fell half a percentage point short of winning the Republican nomination outright, meaning that the two men will face off again on June 24.

But there was no one not being paid by the Cochran campaign who was willing to predict that the incumbent would prevail in three Tuesdays’ time.

Two big reasons.

First, Mississippi Republicans have had the better part of the past four decades to get familiar with Cochran; if they weren’t for him on June 3, what would make them support him on June 24?

Second, Cochran, at 76 years old, looked uncomfortable — at best — on the campaign trail as he desperately tried to restart a political operation that had been dormant for decades. And it’s not entirely clear that his heart is even in it; as Tuesday night turned to Wednesday morning and a runoff looked likely, McDaniel appeared to rally his supporters. Not so Cochran, who was nowhere in sight.

McDaniel’s campaign continues to be dogged by questions — for instance, why was a McDaniel staffer locked in a county courthouse in the wee hours of Wednesday morning? — that may give Cochran a puncher’s chance. But that sort of chance isn’t what a 36-year incumbent should be relying on with less than three weeks left in his career.

Thad Cochran, for going from longtime incumbent to sudden underdog, 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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