Climate change. Student debt. Diversity, equity and inclusion. The war in Gaza.

These topics are central to progressive politics today. They are the subject of campus protests and online debates. They are also almost completely absent from the campaigns of Democratic Senate candidates trying to win tough races this year.

In yesterday’s newsletter, I noted that Democratic candidates are leading the polls in six states where President Biden is trailing — and that all six have based their campaigns around populist themes of defending ordinary citizens against the powerful. Today, I’ll look at some other campaign themes.

One is the contrast between the country’s most heated political debates and the top concerns of most voters. Those heated debates are shaped by policy experts, campaign donors and political activists, all of whom tend to be highly educated and relatively affluent. The full electorate often has different priorities.

Student debt and housing costs make for a useful comparison. Student debt, a subject that the Biden administration has emphasized, may seem like the ultimate pocketbook issue. In reality, it’s more niche: Only 18 percent of U.S. adults have any federal student debt.

That helps explain why, in a recent Harvard University survey of U.S. residents between 18 and 29 years old, student debt ranked dead last when the pollsters asked respondents which of 16 issues mattered to them. Israel and Palestine ranked 15th of 16. Climate change was 12th — and, again, this was a poll of voters under 30. The top three issues were inflation, health care and housing.

No wonder that student debt is largely missing from these Democratic campaigns, while housing — a cost almost every family faces — is a focus. Senator Jacky Rosen, who’s running for re-election in Nevada, has devoted an entire ad to housing costs. Senator Jon Tester’s campaign lists the “housing crisis” as one of Montana’s biggest problems.

A clarifying point about American politics is that people who follow it closely are very different from swing voters. With that in mind, I offer four other themes from the Senate campaigns:

1. Bipartisanship

As polarized as the country is, many voters still hunger for bipartisanship. In their ads, the six Democrats generally treat Republicans with respect and celebrate collaboration.

Senator Sherrod Brown of Ohio boasts about working with Republicans to pass a semiconductor law. Senator Tammy Baldwin of Wisconsin shows videos of Donald Trump and Biden in one ad, and a narrator explains that she worked with both to crack down on Chinese imports. Rosen brags of being “named one of the most bipartisan senators.”

The issue on which the Democrats try hardest to distance themselves from their own party is immigration, which polls show is a major Biden weakness. Rosen tells voters that she “stood up to my own party to support police officers and get more funding for border security.” A Tester ad says that he “fought to stop President Biden from letting migrants stay in America instead of remain in Mexico.”

2. Abortion

Abortion is the opposite. It’s the issue on which the Republican Party is out of step with public opinion — and Democrats are on the offensive.

Rosen describes her likely Nevada opponent, Sam Brown, as “another MAGA extremist trying to take away abortion rights.” Tester, when listing the ways he fights for Montanans, says, “We’ve got folks who want to take away women’s right to choose.”

That said, abortion remains a secondary issue in most of these campaigns.

3. Patriotism

“Growing up poor, the only thing I really had was the American dream,” Ruben Gallego, an Arizona congressman running for Senate, says in the opening line of an ad. “It’s the one thing that we give every American no matter where they are born in life.”

That sentiment is typical of the six campaigns’ unabashed patriotism. Gallego highlights his Marine service in Iraq. Veterans’ health care is a theme of a few campaigns. An ad for Senator Bob Casey of Pennsylvania that is focused on steel includes the line “Take that, China.”

4. Diversity, subtly

The candidates’ ads portray a diverse America. When Rosen talks about housing, she shows a racially mixed group of young couples. A Brown campaign ad about the Ohio steel industry stars both Black and white workers. In a Baldwin ad, a Wisconsin businesswoman with a European accent praises the senator for fighting against federal rules about cheese making. Gallego talks about his mother’s struggles as an immigrant.

But the campaigns treat diversity as a natural part of American life, rather than as a political project. They emphasize the commonalities of Americans with different backgrounds. It’s a different approach from an identity politics that centers race.

Gallego has even achieved some notoriety for mocking the term Latinx. It disrespects the Spanish language, he has said, and is “largely used to satisfy white liberals.” He barred his congressional office from using the term.

It reminds me of a point that Steve Bannon, the far-right political strategist, has made: When American politics focus on race, Republicans — like Bannon and Trump — tend to benefit.

The flip side is that when campaigns focus on economic class, Democrats have the chance to benefit. You can see that lesson in these six populist campaigns.