“Our generation grew up watching as the climate crisis got worse and worse and politicians did nothing.” That might sound like a quote from teen climate activist Greta Thunberg, but it’s actually the opening line for a new series of political ads appearing in multiple states in the lead-up to the 2022 midterms — ads that the advocacy groups Climate Power Action and the League of Conservation Voters are hoping will tip the scales towards climate-focused Democrats.

Historically, however, climate change has not been much of a political kingmaker. Even when candidates trusted that their constituents did care deeply about the environment, it hasn’t been something that reliably changed votes. In the 2020 presidential election, for example, two-thirds of voters told exit pollster Edison Research that climate change was a “serious problem” — but 29 percent of that same group voted for then-President Donald Trump, a candidate whose position on climate change was … inconsistent … at best. 

So a $12 million ad campaign aimed specifically at promoting Democratic candidates’ climate change bona fides seems, at first glance, like a fool’s errand. But even though the content of these ads makes it clear they’re meant for a narrow audience — young voters, who see themselves as part of a generation bearing the consequences of inaction on climate change — the ads aren’t even for all of them. Instead, the groups funding these ads are trying to reach a specific sliver of a slice of a subset of young voters. And yet there’s reason to think that, on those slender margins, climate change could be becoming an issue that really sways elections.

One thing definitely working in favor of climate change as a voting issue this year is the existence of actual legislative change on climate, said Anthony Leiserowitz, director of the Yale Program on Climate Change Communication. Attempts to reach out to voters on climate issues are happening in context with the passage of the Inflation Reduction Act, President Biden’s spending bill that includes a number of tax breaks, new regulations, financing and incentives focused on reducing the country’s carbon emissions over the long term.

The passage of that bill is genuinely a big deal, Leiserowitz said. Outside of that, “there has been little to no major national action on climate change. And I’ve been doing this for 30 years,” he told me. 

The passage of the IRA is in keeping with what voters say they want. A large majority of Democratic voters think the Biden administration and Congress need to be doing more to deal with climate change — 82 percent according to a Pew Research Center survey from May. And that same report found that 58 percent of all Americans felt that the federal government wasn’t doing enough to combat climate change. Given results like that, it would be easy to assume that the passage of a federal bill finally addressing climate would be something that could really motivate voters — at least the liberal-leaning ones.

But the relationship between voters and climate policy has long fallen under the label of “it’s complicated.” There is an established gap between what voters say they want — action on climate change — and what they’re willing to do to achieve that. In 2019, for example, polling by Reuters and Ipsos found that while 69 percent of Americans wanted the government to take “aggressive” action on climate change, only 42 percent were likely to install solar panels on their own home; 38 percent were likely to begin carpooling to reduce emissions; and just 34 percent were likely to pay an extra $100 a year in taxes to support climate policies. And in 13 years of YouGov polls tracking which issues registered voters see as the most important, climate change has consistently taken a back seat to economic issues like jobs and inflation. As of Oct. 10, 12 percent of voters listed climate change and the environment as their No. 1 concern, while 22 percent cited inflation and high prices. It’s not that emphasizing climate change is a turn-off for voters — President Biden got a solid B on Greenpeace’s 2020 election Climate Scorecard. But neither is climate an issue that seems to attract voters on its own. Having the highest score on the Greenpeace scorecard during his candidacy was not enough to catapult Washington’s Democratic governor, Jay Inslee, to the White House.

That history is probably why ads touting climate change policy have been relatively rare this campaign cycle. Of the nearly 350 ad campaigns the University of Virginia’s Center for Politics is tracking in this midterm election, abortion and crime have been the primary issues at play, to the point that the center’s most recent analysis doesn’t even mention climate. Even in the month of September, after the passage of the IRA, ads focused on energy and the environment were still playing third fiddle to other issues like crime and inflation, according to data from the Wesleyan Media Project, which documents details of political advertising. The project found that 15 percent of nationwide political ads in September were focused on energy and environmental issues (which could include climate change), compared to 26 percent of ads focused on public safety and 19 percent on inflation. Even among the ads created by the LCV, some aren’t about climate change or the IRA, specifically — instead talking more broadly about how a specific candidate fits with the Democratic platform. 

But the main goal of the LCV’s ad campaign appears to be persuading people to vote for a candidate because that person has gotten climate policy done — something that’s presented in the ads as a bit of a surprise, a “can you believe they actually did it?” moment. Years of research have shown that the persuasion effects created by advertising — whether political or otherwise — do not last very long, and they are very small, capable of maybe creating a percentage-point difference in swing, said Lynn Vavreck, a professor of politics and public policy at the University of California, Los Angeles. “But don’t confuse small in size with not being pivotal,” she said. 

That’s because while the voting public as a whole has this messy situationship with climate change, there’s a segment of Democratic-leaning voters for whom it is increasingly the real deal. Young and left-leaning voters were most likely to rank climate change as their No. 1 issue in the most recent YouGov poll from Oct. 10. Eighteen percent of voters under 30 and 19 percent of Democrats said it’s the most important issue facing the U.S., compared to 11 percent of voters 65 and older, and just 2 percent of Republicans. And in the ongoing FiveThirtyEight/Ipsos panel survey conducted between April and September using Ipsos’s KnowledgePanel, as much as 36 percent of Democrats named climate change as one of the country’s top issues.¹

Young people have the strongest beliefs about the reality of climate change and the need to take action on it, said Charlotte Hill, a professor of political science at the University of California, Berkeley. That trend is so strong that it even crosses party lines: Forty-seven percent of voting-age Republicans under 30 told Pew in May that the government was doing too little to combat climate change, compared to just 18 percent of Republicans 65 and older. But young (and particularly young, left-leaning) voters are such good targets for these ads because they are also the age group least likely to turn out for a midterm election. And “it’s also pretty consistent that the top reason that young people cite for not voting is not liking the candidates or the issues,” Hill said.

Targeting the people who care the most about climate change, and are the least likely to just go out and vote on their own, with ads that tell them politicians are actually acting on their desires can produce the kind of small differences that tip the scales in some elections, Hill and Vavreck said. 

But the LCV campaign took this one step further, by targeting ads at 2 million specific voters who live in the districts where that tiny margin of change will matter the most, including seven states where the statewide Senate race is a tight one — Arizona, Colorado, Georgia, New Hampshire, Nevada, Pennsylvania and Wisconsin. The model is based off of similar microtargeting work from the 2020 presidential election, when the goal was to persuade undecided voters who cared a lot about climate issues to cast their ballot in favor of Biden, said Pete Maysmith, senior vice president of campaigns at LCV. Those voters approved of Trump more than Biden, but the targeted ads seem to have convinced at least a portion of them to vote Democrat. Based on post-election surveys and a controlled experiment, LCV believes they increased Biden’s vote margin by 5.6 percentage points, relative to the control population. 

Nobody knows yet how big a difference the group will be able to make with this latest round of micro-targeted ads. But evidence suggests that small can be big, and that fact changes the stakes on climate change advertising.