Hickenlooper began the evening with the observation that while Democrats picked up 40 seats in the House in the 2018 midterms, not one Democrat who flipped a district from red to blue did so by running on the kind of agenda that Sanders and Warren are pushing now. It’s a crucial point and a powerful argument against either Sanders or Warren as the Democratic nominee. But neither of the two of them ever directly addressed or specifically rebutted it.

There were smaller contests within the larger one on Tuesday night — for example, Buttigieg versus Beto O’Rourke, 46, for the affections of voters who yearn for generational change. Buttigieg definitely came out on top, in part because he hewed more tightly to the argument that it was time for new approaches and unsullied optimism, capably noting how much of the conversation around him had remained unchanged in Democratic politics for decades. O’Rourke rambled, and the only strong impression of him that I came away with was that he’s tall. His performance won’t arrest his fade from the promise and prominence of his 2018 Senate campaign. He must miss Ted Cruz dearly, and no one ever does that.

Buttigieg’s backers told him before this debate that he needed to show more fire than he did the last time around, after which he stalled in the polls. He didn’t achieve quite the animation that they sought, but he made strides in that direction. At no point during the night did I come so close to standing up and cheering as when he took on Trump’s Republican enablers on Capitol Hill.

“If you are watching at home and you are a Republican member of Congress,” he said, “consider the fact that when the sun sets on your career, and they are writing your story, of all the good and bad things you did in your life, the thing you will be remembered for is whether in this moment, with this president, you found the courage to stand up to him or continued to put party over country.” It was a canned soliloquy, sure, but that made it no less necessary.

Maybe Delaney gets some wind out of the night, although I suspect he’s at such a negligible velocity that it doesn’t matter. Maybe one of the other moderates does, though they became, as the evening went on, not so much individual candidates as a blockade against Democratic socialism, the dizzier dimensions of the Green New Deal and any Medicare for all plan that starts by wiping out private insurance. They raised the right questions about it and poked the right holes in it, prompting Warren to complain repeatedly that they were playing into Republicans’ hands by appropriating Republican talking points.

That was deft of her politically and cheap of her substantively, which made two things abundantly clear.

One, she’s a better candidate than Sanders, at least in the abstract.

Two, if she winds up with the nomination, it will be after planting herself as firmly as possible on an island of purity.

There’s probably no credible toggle toward the center for her, no ready bridge to a messier but potentially bigger mainland. What bold real estate. What risky terrain, too.

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