In a best-case scenario, she breaks Biden’s hold with African-American voters and convinces white progressives that she’s a stronger candidate than Warren or Sanders. But if she struggles in the overwhelmingly white confines of Iowa and New Hampshire, she won’t be able to rely on goodwill from moderates to get her back in the game.

A Biden collapse would also create a small opening for the two pragmatic senators— Minnesota’s Amy Klobuchar and Colorado’s Michael Bennet—who impressed on the debate stage. Bennet didn’t join his colleagues who wanted to decriminalize illegal immigration, but made a moving case against Trump’s nativism. Klobuchar sounded a skeptical note regarding Warren’s ambitious government programs, but didn’t attack her directly. Both senators have track records of winning over Republicans in swing states.

Pete Buttigieg, with another winning performance on the national stage, may also get another look from voters despite his struggles back home. He managed to support liberal goals without taking extreme measures to accomplish them.