WASHINGTON — Climate change has recently shot to the top of polls of issues that Democratic voters care about in the presidential primary, rivaling for the first time longstanding bread-and-butter topics like health care — and a leading environmental group has plans to keep it that way.

That's a big shift from the last presidential election in 2016, when climate change did not get a single question during the debates between Hillary Clinton and President Donald Trump, and just 15 percent of Democratic primary voters named it as their top priority.

"Health care and the environment are clearly the top issues in this race, but it doesn’t look like any candidate owns a clear advantage on them," said Patrick Murray, the director of the Monmouth University Polling Institute.

That's created an opening both for candidates and for activists, who have had trouble in the past making climate change a voting issue.

The League of Conservation Voters (LCV), the deep-pocketed green group that spent over $80 million in last year's midterm elections, aims to ensure climate is not just a priority, but the highest priority for 2020 candidates, with a new campaign to influence the contest backed by an initial $2 million investment called Change the Climate 2020.

"We want to see a race to the top between the candidates when it comes to combating climate change," Tiernan Sittenfeld, the group’s senior vice president for government affairs, told NBC News. "It's an issue that clearly hasn't got the attention it's deserved for far too long. That's changing and not a moment too soon."

The Change the Climate campaign will include both online and offline advocacy to pressure candidates, including staff organizers who have already been deployed to New Hampshire and Nevada and recruited some 700 volunteers in those early-voting primary and caucus states. A similar effort in South Carolina is next.

Natural disasters and the Trump administration's refusal to combat climate change have added political urgency to the issue among Democrats. As has the more confrontational tactics of grassroots groups like the Sunrise Movement and Rep. Alexandria Ocasio Cortez, D-N.Y., who joined a climate sit-in in House Speaker Nancy Pelosi’s office during one of her first days on Capitol Hill.

Washington Gov. Jay Inslee, a Democrat who has based his entire presidential campaign around making climate a top issue in 2020, told NBC News on Tuesday that he sees a political "magic moment," where heightened fear about the climate has met new technologies that offer hope to solve it.

"What used to an intellectual abstraction is now a visceral life event for people in real time," Inslee said before signing a new clean energy bill. "It's not about their grandchildren, it's about them — standing knee-deep in water or watching their house burn down."

Parts of Iowa, which holds the first presidential primary caucuses early next year, are still underwater from catastrophic floods, while California, which will play a newly important role in the presidential primary, just had its deadliest and most destructive wildfire season of all time.

With that backdrop, groups like League of Conservation Voters want presidential candidates to go further than they have in the past, when climate change was often seen merely as one of many boxes to check.

They were heartened, for instance, that former Rep. Beto O’Rourke chose to make a $5 trillion climate plan his first major policy rollout, while many candidates are amping up their rhetoric to show they take the issue seriously. Sen. Kamala Harris, D-Calif., said on MSNBC on Tuesday that climate change "represents an existential threat to who we are as a species."

"Ambition, prioritization and bold plans that match the scale of the crisis are essential, as is the recognition that this is something that they have to get to work on on day one of their presidency," said Pete Maysmith, the League of Conservation Voters’ senior vice president for campaigns.