Donald Trump and Hillary Clinton could not be more different on climate change. Yet, it took a guy in a red sweater to get them to even touch the issue in a debate.

Ken Bone, the coal plant operator and undecided voter who won the internet during the second presidential debate with his sweater and disposable camera, asked Clinton and Trump how they would embrace clean energy while protecting jobs.

Trump responded largely by criticizing the Environmental Protection Agency and international steel dumping and vowing to "bring our energy companies back." Clinton called climate change a serious problem but talked more about making the U.S. the "21st century clean energy superpower" while not abandoning coal country.

The phrase "climate change" surfaced only once, just like in the first debate when Clinton claimed Trump believed climate change was a hoax. It got another mention in the third debate when Clinton again spoke of climate change as an opportunity for clean energy jobs.

That's been pretty much it on an issue where it feels like every voter has an opinion but no politician really wants to take it head-on.

Few candidates running for national or local offices seem willing to push climate change into the spotlight — no matter their views. In the three presidential debates, not a single question about climate change was put to Clinton or Trump, although it was on the list of crowd-sourced questions moderators could have asked in the second debate.

One reason may be that polls show the complex issue more polarizing than abortion. Those who've tried to talk about climate change and science have felt the sharp elbows from both sides.

Meteorologist Paul Douglas speaks about climate change during the University of Minnesota's annual Kuehnast Lecture in October. Elizabeth Dunbar | MPR News

"People come up and say, 'Paul what's wrong with you? You're a Republican, you're a conservative, you're a Christian, how on earth can you latch onto this liberal meme of climate change?'" said Paul Douglas, a former Twin Cities TV meteorologist who frequently gives public talks about the evidence for climate change, often to crowds that likely include doubters.

He quotes Ronald Reagan on care for the environment and brings up free enterprise and national security arguments for climate action. After speaking at an event at the University of Minnesota earlier this month, he said he couldn't vote for Trump, "a climate science denier." So he's supporting Hillary Clinton this year. He says he's not thrilled about it.

"Sometimes we have to hold our nose and do what we think is right for the next generation as well as this generation," he said.

Trump has rejected the scientific consensus that climate change is real and mostly caused by burning fossil fuels while Clinton has declared climate change an urgent threat and outlined a plan to cut carbon emissions drastically, while charging Trump is a science denier.

Solar panels used by the city of Hutchinson to power the waste water treatment plants built on an old landfill, March 29, 2016. Elizabeth Dunbar | MPR News File

Those who've made addressing climate change a priority applaud Clinton but still worry the issue isn't getting the attention it deserves.

Too many Democrats have ducked the issue, said RL Miller, president of the political action committee Climate Hawks Vote, which is backing about a dozen or so congressional candidates this year who make climate change one of their top priorities.

Miller, who chairs the environmental caucus for the California Democratic Party, says she's lost hope that Democrats and Republicans can work together to address climate change.

"I want to reject the idea that if we just frame things nicely, we can reach across the aisle to Republicans," she said. "If you don't put climate change as a top issue, it will remain on the back burner."

It's getting more difficult, however, to find Republicans who outright reject climate change science the way Trump has. It's more common for them to say they don't know if they believe in the science. That's what GOP congressional candidate Jason Lewis said during the Minnesota 2nd Congressional District debate on MPR News last week.

2nd Congressional District candidates Jason Lewis and Angie Craig prepare to debate with moderator Tom Weber at MPR studios in St. Paul on Oct. 20, 2016. Evan Frost | MPR News

Lewis questioned investments going toward the transition to make energy sources carbon-free.

"In this cost-benefit analysis, which we have to look at in all environmental regulations, is it worth it?" he asked. "Is it worth lowering Celsius half a degree over the next 100 years, half a degree of temperature, all for $500 billion?"

Those pushing the carbon-free transition say the costs of inaction are far greater, especially if you factor in the public health benefits of retiring power plants in favor of renewable energy.

MPR Special event: The impact of climate change on public health

Some in the GOP believe addressing climate change fits well with the party's bedrock belief in capitalism and that the party will see that should Trump be defeated.

Bob Inglis, a former Republican congressman from South Carolina, speaks about conservative solutions to climate change during the U of M's annual Kuehnast Lecture on Oct. 12, 2016. Elizabeth Dunbar | MPR News

"I'm hoping for a crash and a burn, and then we start over. Out of those ashes comes the Grand Opportunity Party, which actually believe in the power of free enterprise," said Bob Inglis, who served in the U.S. House for South Carolina until he was trounced in the 2010 GOP primary after calling for a revenue neutral carbon tax to address climate change.

The lack of discussion of climate change frustrates voters like Joyce Prudden of St. Louis Park, who considers it "the great problem of our time. This is much more important than worrying about ISIS and whether we have a few Mexicans crossing the border," she said. "This is going to affect a lot of things."

At the local level, however, finding candidates and voters willing to listen and talk about climate change remains a challenge. Only seven of more than 120 Minnesota state senate candidates even mention climate change on their campaign websites, MPR News found.

"These aren't the top priorities for people," said Paul Anderson, a Republican running for an open state Senate seat in the west metro. While energy and climate are important topics, he says that in nearly six months of door knocking, only a couple of voters have raised the issue.

DFL state Senate candidate Deb Calvert talks with resident Timothy Hlas on October. 21, 2016 in Plymouth. Sam Harper | MPR News

"We have to focus on what's important to the people and getting back to getting things done at the state Capitol," he said. "If we don't focus on those core things and make sure our economy is strong and our schools are strong and our health care is strong, then the other things don't matter to begin with."

Anderson's Democratic opponent sees it differently. Deb Calvert is one of the few state Senate candidates who've made climate change part of the pitch to voters, arguing that by addressing climate change, Minnesota and the country can head off more serious problems.

"It really does have economic implications," she said. "It has geopolitical, strategic, defense implications and it should not be politicized. This is something that affects our entire planet."