But Iowa’s stakes may be higher than the candidates’ cautious strategy would seem to indicate. Link is one of several Democratic strategists who thinks that all of the campaigns are underestimating how powerfully the Iowa results may reshape the rest of the race. He believes the risks for the others are especially great if Sanders wins, because a victory here would likely further turbocharge the senator’s fundraising operation, which is already swamping those of his rivals. “There’s a kind of lack of urgency between Warren and Biden and Buttigieg and Klobuchar,” Link said. “Anyone who thinks it’s okay to let Sanders win anything is miscalculating.”

Biden may be best positioned to withstand a disappointing Iowa showing, because his strength with black voters guarantees him a solid shot at winning South Carolina regardless of how he does tonight, but some believe a weak finish could still precipitate a powerful downward spiral by triggering the party establishment to unify behind another moderate candidate.

At most of the campaign appearances across Iowa I’ve been to during the past several days, the candidates have rarely, if ever, mentioned their rivals. By the standards of earlier Democratic races, this is something like bringing a butter knife to a gunfight.