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BURLINGTON, Iowa—A crush of new Democratic voters, mobilized by a wave of anti-Trump energy, will arrive at their caucus precinct, and there will not be enough voter-registration forms. The lines will be long, and some Iowans, many of them elderly, will shiver in the cold for hours before getting inside. The caucus itself will be pandemonium: There won’t be enough preference cards for caucus-goers to write down their favorite presidential contenders. Voters will be incensed when they learn about the new realignment rules. There will be miscounts and recounts. And at the end of the night, once all the numbers have been crunched and recrunched, Joe Biden, Elizabeth Warren, and Bernie Sanders will each claim victory.

This is Sandy Dockendorff’s nightmare scenario for tonight’s caucus. The 62-year-old former nurse, who is running a caucus in the small town of Danville, laid it all out for me over coffee last week. Her worst fears are unlikely to be realized. “The party has done everything it can to make sure that’s not the case,” she said. But the caucus is extremely complex, and rule changes threaten to make it even more bewildering for voters to navigate and complicated for the press to cover. The biggest fear: Democrats may not have a clear winner—a scenario that could further threaten Iowa’s imperiled first-in-the-nation position.

“Caucus chairs are more concerned this cycle than I’ve ever seen them,” Dockendorff said. “They’re very nervous.”

Dockendorff has organized and led a dozen caucuses since she moved to the state from Virginia in 1996, and she’s used to being a keeper of caucus knowledge. She gets a lot of questions about the caucus from confused Iowans and out-of-state reporters, and she delights in the intricacies of the process. Sitting across from me at a café in Burlington, wearing purple glasses on her face and sunglasses on her head, she used a piece of paper to illustrate a set of realignment scenarios. While we spoke, a middle-aged woman came over to our table and sat down, hoping Dockendorff could help assuage some of her fears: “I heard some really scary news on Twitter today about the caucuses!”

This year, Dockendorff has fielded a lot of questions. The parties have run the caucus the same way for decades: Voters show up to an assigned precinct—a church or an elementary school in their neighborhood, say—and stand under a sign or in a corner associated with their favorite candidate. For half an hour, people hustle between groups, trying to coax fans of other candidates to join their team. Then organizers count each candidate’s supporters, and there is a realignment period, during which people can switch allegiances. Members of any candidate group that doesn’t get at least 15 percent of caucus-goers must move to a new candidate. Once this part is done, delegates are assigned to the remaining contenders using a mathematical formula, and reported to the state party.

For the 2020 contest, though, there are a few major changes. Caucus-goers who choose a viable candidate in the first round can’t switch. For the first time ever, voters will write down their choices on preference cards, in case there’s a recount. If a precinct has only a small number of delegates to give out, even supporters of viable candidates may have to realign; which group realigns could depend on a coin toss. (The state party instructs caucus chairs to bring their own quarter or some “other method to conduct a game of chance.”) “Some precincts have three delegates, and it’s not inconceivable that five candidates are viable,” Dockendorff said.

But the most crucial development this year is that each of Iowa’s 1,700 precincts is required to report two data points in addition to its final delegate count: the totals each candidate received in the first count and the totals they received after the first realignment.

Releasing these numbers is meant to add transparency to the process. But the new rules make it more likely that several Democratic candidates will claim victory on Monday. The traditional winner—the Democrat who receives the most delegates—will be able to boast the best organizing strategy in Iowa. But it’s about more than just delegates, Dockendorff said. “There’s going to be somebody who’s going to be able to say, ‘Look, we had 1,000 more people show up to the caucuses for us. Obviously we’re the strongest,’” she explained. And the candidate who ends up with the most total supporters after the realignment—when voters from unviable groups find a new group—can brag that he or she has built the broadest coalition of support, or has the most persuasive organizers.

Releasing three results “could be a huge problem,” Steffen Schmidt, a political-science professor at Iowa State University who has taught classes about the caucus, told me. Being able to spin any combination of results into a win will make it easier for candidates to stay in the race through New Hampshire and beyond, even though the Iowa contest typically serves as a way to winnow the primary field. “I don’t get why, instead of transparency and simplicity, the party has gone deeper into great complexity and resulting confusion,” Schmidt said. Other caucus leaders are worried too. I talked with Reyma McCoy McDeid, an activist in Des Moines who is running a satellite, or remote, caucus for voters with disabilities, about what she expects on caucus night. “Oh, God,” she said with a laugh. “In 2016, there were three candidates, and it was mayhem. We have how many candidates now? … Caucus night is going to make 2016 look like a cakewalk.”

People like McCoy McDeid and Dockendorff, who are volunteers, already have a lot to handle. They’ll be balancing several sets of paperwork, using math formulas to calculate candidates’ viability and apportioning delegates. Now they’ll also have to reexplain the rules and the results for caucus-goers. “There are going to be so many people who have been through caucuses for years who don’t realize that the rules have changed,” Dockendorff said. Many of these voters “are going to have an absolute conniption fit.”

Is the caucus really worth all this trouble? I asked Dockendorff. Obviously, the contest brings attention and resources to the small state that wouldn’t otherwise have either. But as I’ve written before, Iowa’s prominence in the primaries is under harsh scrutiny from critics who argue that the state is too white to be representative of the Democratic Party writ large and that the caucus system itself is inaccessible to many, including people with disabilities. Dockendorff acknowledges that those problems are serious. But ultimately, the caucus process is not only valuable but necessary, she told me. “The kind of candidate that can win in Iowa is the kind of candidate I want to see in the Oval Office,” she said. A candidate “can’t be but a better human being for having been assaulted with this humanity in its purest form.”

If Iowa hopes to maintain its privileged status, it’s crucial that everything go smoothly tonight. During the 2016 caucus, volunteers were unprepared for the overwhelming turnout; there were technological problems, reporting errors, and multiple coin flips. Hillary Clinton beat Bernie Sanders by 0.25 percent—the closest margin in Iowa history—which led many Sanders fans to accuse the state party of putting its thumb on the scale for Clinton. Another chaotic caucus could be the final straw for the contest’s credibility. And Dockendorff believes that many Americans are rooting for the caucus to fail. If the party process doesn’t work, she said, “some people who are not fans of the Democratic Party will feel vindicated.”

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