Former New York City Mayor Rudy Giuliani
As always, showed up without any strategy to win—on the night he most needed to win big. Offered shrewd, vigorous answers but without a schematic purpose that would define a rationale and theme for his candidacy. Nevertheless, he was a cool customer, with the same unflappable, calm delivery he has presented in every debate for nearly a year, regardless of polls, news-of-day, or media expectations. That persona was good when he was the national frontrunner, but on the eve of the most important election of his presidential career, it just wasn't good enough.
—By Mark Halperin