A few weeks ago, the pollsters at Monmouth University asked Democrats across the country to choose between two different kinds of nominees. One was a candidate whom the voter agreed with on most issues but who might struggle to beat President Trump. The other was the reverse — a strong candidate with different views from those of the person being polled.

It was a rout. About 56 percent preferred the more electable candidate, compared with 33 percent who picked the more ideologically in-sync candidate. The gap was even larger among women and liberal Democrats. Patrick Murray, who runs the Monmouth poll, points out that this pattern isn’t normal. In previous campaigns, voters cared more about ideology than electability.

I think there are two main reasons for the switch. The first, of course, is the awfulness of the Trump presidency. But the less obvious reason is important too: The differences among most of the leading Democratic presidential candidates just aren’t very big right now.

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They all favor policies to lift incomes and reduce living costs for the middle class and poor. They all favor tax increases on the rich. They all favor climate action, voting rights and expanded Medicare. Most voters understand that choosing a candidate with modestly different ideas about how to achieve these goals isn’t much of a sacrifice.

So if Democrats wanted to identify their best hope for beating Trump, what would that candidate look like?

Above all, it would be a candidate good at persuading Americans that he or she was on their side — on their side against the forces causing the stagnation of American living standards. More specifically, this candidate would be someone who could persuade swing voters of this allegiance.

Swing voters still exist. Enough Americans switched from backing Barack Obama in 2012 to Donald Trump in 2016 to House Democrats in 2018 to help decide those elections. I understand why some Democratic activists are instead drawn to the idea of victory through turnout: It offers the promise of avoiding any political compromise. The problem is, there are virtually no examples of Democrats winning close races without emphasizing persuasion. The 2018 attempts, in Florida, Georgia and Texas, all fell short.

Yet progressives shouldn’t despair — because swing voters are quite progressive, especially on economic issues. For years, we’ve been hearing about a kind of fantasy swing voter, conjured by political pundits and corporate chieftains, who is socially liberal and economically conservative (as many pundits and chieftains are). The actual swing voter leans decidedly left on economics, in favor of tax increases on the rich, opposed to Medicare cuts and skeptical of big business.