President Biden has done more than any president to tackle climate change, but strategists are grappling with an uncomfortable fact: Voters don’t seem to know it.

Mr. Biden has orchestrated the biggest ever federal investment in clean energy and electric vehicles and has proposed what would be the first limits on planet-warming pollution from power plants as well as the tightest restrictions on tailpipe emissions. He is cracking down on methane, a potent greenhouse gas, that leaks from oil and gas wells. Taken together, these efforts could substantially reduce the country’s contribution to global warming.

But as he faces a bruising re-election campaign against the Republican front-runner, former President Donald J. Trump many Democrats said the president is failing to communicate his most significant policy achievements.

In recent months, polls have found that most Americans are unaware of the Inflation Reduction Act, Mr. Biden’s signature climate law. Of those who have heard of the law — with a name that has nothing to do with climate — few know that it marks the federal government’s biggest attempt to cut the greenhouse gases that are dangerously warming the planet.

The 2022 law provides at least $370 billion to reduce carbon pollution by boosting the production of wind, solar and other renewable energy, and providing millions of dollars in tax credits to homeowners and consumers to move away from fossil fuels.

That’s consequential because nearly seven out of every 10 people who voted for Mr. Biden in the last presidential election said climate change was very important to their vote. According to a poll last month from The Economist/YouGov, 18 percent of those Biden voters from 2020 now list climate as their top priority.