At the same time, she seems to have little special resonance with less educated voters, even though her policies would seem to be targeted at building their support. For now, technocratic populism could be a lose-lose.

The challenge extends to nonwhite voters; she underperforms Mr. Biden by even more among this group. Here, she does have a name recognition problem: 32 percent of the 87 nonwhite Biden-but-not-Warren voters in our polls don’t have an opinion of her, and they agree only narrowly, by a margin of 38 percent to 30 percent, that she’s too far to the left. But those who do have an opinion generally don’t think highly of Ms. Warren, with 24 percent favorable and 43 percent unfavorable.

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These nonwhite Biden-but-not-Warren voters split, 44-46, on whether they agree with the statement that the women who run for president just aren’t that likable. Unlike other nonwhite voters in the surveys, they split on whether they support reducing legal immigration. Ms. Warren will most likely win some of these voters, but they will offer resistance to a progressive nominee.

There is not much difference between a strategy based on turnout and persuasion.

It’s commonly assumed that there’s a simple choice between persuasion and turnout in elections: A candidate can either aim to flip moderate voters or to rally a party’s enthusiastic base.

In a high-turnout presidential election, this choice doesn’t really exist. Virtually all of the ideologically consistent voters will be drawn to the polls, at least in these crucial states where the stakes are so high.

As a result, the voters on the sidelines are often also persuadable. With the exception of one key chunk of persuadable voters — affluent voters repelled by the left on economics — the persuadable voters wind up looking fairly similar to the low-turnout voters.