The downside risk of losing this election is greater than it was in 2008, and for many Democrats, the desire to mitigate that risk is the decisive factor drawing them to Clinton’s campaign. But if Sanders’s candidacy is genuinely reckless, his critics must be more persuasive than they have been on that point. Otherwise, the fact that the Sanders bloc is large and growing simply reflects ideological divisions within a party that is structurally favored to win the presidency anyhow. And if that’s the case, going all-in for a progressive champion might just be worth it.