If you don’t know the math of how many voters each candidate needs to gain a delegate’s vote, and you don’t know which candidate you want, it’s extremely difficult to be strategic.

“But if it’s too much like a primary, we lose our first-in-the-nation status,” Ms. Bribriesco said when I asked her if the Democratic caucus process needed to change. She spoke positively of it all despite the fact that this year, the caucus site she will attend in Bettendorf will include 12 precincts packed into the Quad Cities Waterfront Convention Center.

Kathy Laird from Bettendorf (who happens to be Ms. Bribriesco’s cousin) recalled that in 2016, she had chosen Mr. O’Malley during the first round but had to choose between Mr. Sanders or Mrs. Clinton after Mr. O’Malley didn’t gain enough voters and was ousted from the ballot. The four Iowans in the O’Malley group were bombarded by supporters for the other candidates trying to convince them to join. Usually, voters get around 15 minutes to decide. But things would be different this year, with 12 candidates to choose from. She expects pure chaos to reign.

In the last election cycle, Mrs. Clinton and Mr. Sanders were almost exactly matched — with the tip to Mrs. Clinton by a 0.3 percent margin — and in individual precinct counts, numbers are rounded up and down to determine whether someone receives a delegate vote.

How can we trust the Iowa indicator?

Ms. Bribriesco said that in 2016, getting a total head count for each candidate was like “herding cats.” This year, at least, there are paper ballots to keep track of the number of people in each candidate’s corner. This way, people whose candidate moves on can leave after the first round; the paper becomes their placeholder, and votes can’t be changed after the second round.

Some precincts, we learned, would flip a coin or draw straws to break a tie. It was disillusioning to hear that some delegate votes were left up to chance, given how close the caucus was last time — even if now most people agree that the luck of the draw couldn’t have changed the outcome of 2016.

Two newcomers to the party at the caucus training, the former registered Republican Dave Scott from Bettendorf and his wife, want to beat President Trump, even if it means putting a Democrat in the house.