It's not just candidates who are being winnowed; it's voters

Marco Rubio speaking with a catch in his voice to a small Miami audience of die-hard supporters — and people in the audience openly weeping, hugging, hanging their heads — will be one of the most poignant images I will carry back with me when my tour of primary states is over. This is an image of people being left behind by the relentless logic of the U.S. political system.

In the last two months, I have talked to a slew of knowledgeable people in six early-voting states, and also in New York and Washington, D.C., who claimed not to understand what's going on in this election campaign. All bets are off, they said; all the rules are out the window.

I shrugged this off. What I saw in the early-voting states was a genuine, grass-roots democracy with hundreds of thousands of engaged voters. They don't know or follow the "rules."

One could juggle horse-race statistics, point out that no previous candidate had ever won the presidency without carrying this or that state, discuss obscure rules that could help turn losers into winners under certain circumstances. That's what experts do. Ordinary voters, though, weren't into any of this. They were just expressing their preferences along clear lines that suggested the U.S. really had far more strains of political thinking than two major parties represented.

I talked to them, and it became clear to me that Iowa and South Carolina evangelicals really did identify with Ted Cruz; that independent-minded New Hampshire voters really connected with the experience-based messages of John Kasich and Jeb Bush; that Colorado Democrats did believe, with all their heart, in Bernie Sanders's promise of a revolution that would put a certain kind of justice at the center of American life. Their voting wasn't strategic or calculated; they voted their values.

Too few Floridians backed Rubio for him to carry his home state, but these people really did believe in his version of the American dream. Some, like him, were Cubans, exiles and children of exiles. They wanted one of their own to win the big prize; even as he announced he was suspending his campaign, they shouted "Don't give up!" and "We don't want any other president, just you!"

Most of these people will not vote for Donald Trump in November. They will not be compelled by some abstract notion that Republicans must come together, strategically, to beat Democrats. I asked them, and they said, "Never." When a pro-Trump heckler disrupted Rubio's concession speech and was led out, muttering, "Loser, lose," they snatched his red "Make America Great Again" cap and tossed it contemptuously around the hall.

Similarly, many of those Sanders supporters in Colorado, who want radical change rather than more patches on the existing quilt of a social safety net, will not transfer their enthusiasm to Hillary Clinton, whom they're finding hard to trust. Some might vote for her, as their second-best option from the 2016 field. Others, though — and I'm guessing the youngest and most maximalist — will not vote at all in November, having been motivated only by Sanders.

There has been a lot of talk of winnowing during the first phase of the election campaign. But it's not just the candidates who are being winnowed. It's also the voters. The logic of the two-party system forces voters to either drop out or vote strategically, as if this were a game rather than an expression of values. In this game, the person who draws more of these strategic votes wins, regardless of what he or she stands for.

The system's additional requirement is that the race be watchable. The media, which are largely not interested in covering the election as anything but a sports contest, are working to set up the most spectacular one. That is definitely Clinton vs. Trump. The Democrat has her obvious, highly telegenic inner struggles. Oh, and she's a woman. Women in the audience definitely want a woman on the show. The Republican is easy to demonize, and he's a professional at the media game, playing the charming villain as no one else could.

John Kasich may have won his home state of Ohio, and Ted Cruz won his in Texas, but they don't meet both requirements: ratings power and the support of strategically minded crossover voters.

Within the constraints of the two-party system and the demands of the TV script, all the seemingly chaotic activity of the primary season appears to be setting up a Clinton win over Trump: She draws more strategic voters, and the villain, no matter how charming, is never supposed to win in the end.