First, it’s quite possible that Biden could win Iowa outright, and in doing so basically wrap up the nomination early. Biden’s early Iowa swoon has been reversed, he’s leading the Real Clear Politics polling average and is even with Sanders in FiveThirtyEight’s average, and Elizabeth Warren and Sanders seem headed to war with each other as the race enters the final stretch. Which could set up a de facto replay of 2004, when Dick Gephardt and Howard Dean dragged each other down and John Kerry won an Iowa victory that set him up for an easy glide to the nomination.

Would Biden cruise as easily as Kerry? Maybe not: Sanders has the money and passion for the long delegate-accumulating march, Bloomberg and his billions are waiting, and maybe an Iowa victory would prompt an anti-Biden consolidation (says the pundit who spent 2016 waiting for an anti-Trump consolidation that never came). But given Biden’s strength with nonwhite voters, his stable national lead and his perceived electability, if neither of the left-wing candidates can beat him in Iowa, can they really expect to beat him on Super Tuesday? Similarly, if a smooth Indianan in Pete Buttigieg and a cheerful Minnesotan in Amy Klobuchar can’t peel moderates away from Biden in Iowa, can a grouchy New York zillionaire really expect to pull it off weeks later? The likely answer to these questions means that if Iowa votes for the former vice president, it may have picked the nominee.

In the second scenario, Sanders could win Iowa, Biden could finish a close second, and the campaign thereafter could quickly become a two-man race — with Klobuchar finished, Warren and Buttigieg fading, and no room for Bloomberg in a polarized left-versus-establishment contest. The parallel here would be to the Republican race in 2016, when Ted Cruz’s Iowa victory made him the anti-Trump standard-bearer, and despite a few Marco Rubio Moments thereafter it was basically Donald Trump against Cruz the rest of the way. In this scenario, Iowa wouldn’t have picked the winner outright, but it would have picked the final two and disposed of every other candidate in a single evening.

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In the third scenario, Warren could rally to win Iowa — an outcome less decisive for the field’s consolidation because of Sanders’s money and grass-roots strength, but one that would dispose of Buttigieg and Klobuchar and make it likelier that Warren surges past her democratic socialist rival in New Hampshire as well. If Sanders dropped out after that, the rest of the campaign would be a Warren-Biden tilt, in which case Warren would owe everything to Iowa; if Sanders stayed in it could be an easy coast for Biden, who would have Iowans to thank for letting him run against a persistently divided left.