(CNN) Politics is, at root, governed by a simple proposition: You can't beat something with nothing.

In short: No matter how bad a candidate is, you have a 0% chance of winning if you don't run against him or her. You miss all the shots you don't take. You can't win if you don't play.

All of those cliches tell us something very important about the midterm election in 12 days -- and why, despite all of the talk that the Democratic wave is receding, there's a not-unreasonable case to be made that the minority party could rack up even larger seat gains than currently being estimated.

Republicans currently hold 235 House seats. There are 36 GOP members either retiring or running for some other office in 2018. That leaves 199 GOP incumbents seeking re-election -- all but 10 of whom have drawn Democratic challengers. That's remarkable, as Brookings' Michael Malbin notes in his piece on the data -- writing: "The average number of uncontested seats in one or the other party since 2004 has been 54. The next lowest numbers were more than twice this year's figure."

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