In an email, Yascha Mounk, a lecturer in government at Harvard, wrote:

One of the dangers for the Democratic Party — and the left-leaning parts of the establishment more broadly — is that they confound their actual audience with a small but highly visible group of activists.

Mounk argues that

a majority of Americans is horrified by hate speech; disgusted by the Trump administration’s attacks on immigrants; and committed to the fight against sexual harassment. But a majority of Americans also feels that ‘call-out culture’ often attacks people for innocent mistakes and that some attempts to remedy racism actually serve to divide the country further along racial lines.

Strategically, Mounk contends,

If Democrats couch their fight against the evident injustices that still persist in our country in universal language that has deep roots in the American tradition, they have a good chance of winning elections — and making a real difference for the most vulnerable members of our society. If, on the contrary, they become captured in language games that are only understood by the most political and best educated progressive activists, they are likely to alienate a lot of potential supporters — including a large number of women and people of color.

In many respects, the issue of immigration embodies the Democrats’ problem.

According to Pew, Democrats share with much of the general public a positive view of immigrants. 65 percent of all Americans agree that immigrants strengthen the country compared with 84 percent of Democrats and 42 percent of Republicans.

While the immigration data suggests that Democrats should not have a significant problem with the broad issue of immigration on Election Day, the numbers mask a more subtle reality. Men and women opposed to immigration are much more likely to vote Republican on the issue than supporters are to base a vote for a Democratic candidate on a pro-immigration position.

That is one of the reasons that even after the backlash on Trump’s child separation policies, Republicans have continued to emphasize anti-immigration policies. Republicans are “painting Democrats as the ones pursuing an extreme immigration agenda that would fill the country with sanctuary cities’ where violent criminals roam free,” my news side colleague Julie Hirschfeld Davis wrote in The Times on Oct. 14:

Democrats have found that in politically competitive states, particularly ones that Mr. Trump carried in 2016, the attacks can easily turn crucial voting blocs against Democrats.

The ongoing mobilizing force of the immigration issue raises a question for Democrats that never disappears completely: how far can the party push an agenda of social liberalism while keeping the support of at least 50 percent of the voters, plus one?

Lee Drutman, a senior fellow in the political reform program at New America, wrote me by email:

The danger for Democrats is that the electorate overall is probably still a little right-of-center on social issues, and older voters who vote at consistently higher rates are decidedly conservative on social issues. To the extent that these issues define elections, especially Senate elections (where conservative rural voters matter more), Democrats are at a disadvantage.

The party’s strengthened social liberalism may help Democrats mobilize more left-leaning Gen Y and Gen Z voters (those between the ages of 18 and 28), Drutman pointed out, which would be crucial. But Drutman added a cautionary note for liberal enthusiasts: “Democrats have consistently been disappointed by hopes of mobilizing younger voters, particularly in midterms.”

And here’s another cautionary note: the very nature of political polarization suggests that even as liberals pull sharply to the left, conservatives are pulling sharply to the right, and it is unclear who will win the tug of war.

I invite you to follow me on Twitter, @Edsall.

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