Pledged delegates

Finally, there are pledged delegates to the Democratic National Convention, awarded based on the number of state delegate equivalents won by each candidate statewide and by congressional district.

In the past, these results weren’t available on election night either. Before this year, the state convention could elect whomever it wanted to the national convention, regardless of the results at the precinct caucus. Now, the pledged delegates to the national convention are bound to the state delegate equivalency results, so we will know right away who wins the most pledged delegates as well.

Strangely enough, the candidate with the most state delegate equivalents is not guaranteed to have the most pledged delegates.

There are two major reasons there could be a split at this late stage. One is the 15 percent threshold to win delegates in a congressional district. If the second-place candidate managed to clear 15 percent in all four districts, while the winning candidate fell short, the second-place candidate would stand a good chance of leaping ahead.

The winning statewide candidate will probably clear 15 percent everywhere, but this scenario is conceivable in such a closely fought contest and with so many candidates in the race. It could well center on the Fourth Congressional District, a mostly working-class, conservative and rural area in the northwestern part of the state. A candidate who won Iowa by dominating liberal enclaves could conceivably do quite poorly here. Nonetheless, in this simulation all of the leading candidates clear the 15 percent threshold.

The more likely way the pledged delegates could differ from delegate equivalents hinges on the number of noncompetitive candidates earning 15 percent of the vote. A candidate’s delegate haul in a district could shrink quickly if too many candidates breach 15 percent and become entitled to delegates. In our scenario, Ms. Warren breaches 15 percent in the Third District, and earns a delegate that would have otherwise gone to Mr. Buttigieg.

Another major reason is rounding. Basically, the number of delegates awarded by district or statewide is quite small. Whether a candidate earns an extra delegate here or there comes down to clearing thresholds that vary depending on the number of delegates per district.