The worst idea is to try to out-Trump Trump. This is the approach Wisconsin Gov. Scott Walker — who may be suffering the most from the Trump surge — is trying to take.

Back in March, Walker briefly led all comers in the national polls. As recently as a few weeks ago, he was still ahead in Iowa — the state where he has basically placed all his chips. If Walker can’t win in the Midwest, he probably can’t win anywhere. Until recently, the only question was how big his Iowa margin would be.

But Walker’s numbers in his must-win state have plunged as sharply as Trump’s have risen. In the RealClearPolitics polling average, Walker is now in fourth place. In a recent CNN poll, Walker’s support in Iowa was down to just 9 percent while Trump led the field with 22 percent. This wasn’t all Trump’s fault: Walker’s performance in the first debate was forgettable and his stump appearances had become repetitive, almost robotic. Voters knew, already, that organized labor had tried to take him down, but he was still standing.

In desperation, Walker has begun trying to sound more like Trump.