Over the last year, support for nuclear power has grown. Whether it’s Republicans in Illinois or Democrats in New York, policymakers are finally starting to treat nuclear the same way we treat other sources of clean energy.

But now, our efforts to protect America's largest source of clean energy are under fire.

Environmental Progress has discovered that American Petroleum Institute — Big Oil — is spending millions to bombard voters in Pennsylvania with direct mail, spread misinformation in Ohio, and twist the arms of legislators.

Big Oil is blanketing Pennsylvania with its propaganda. Even EP science advisor, the climate scientist James Hansen, received one of the mailers.

We gave the information to the Wall Street Journal, which published the exposé today:

Some environmentalists are applauding state support for nuclear power.

“We need to have a fair system,” said Michael Shellenberger, president of Environmental Progress, a pro-nuclear policy center, who first publicized the oil lobby’s involvement.

Mr. Shellenberger said that if renewable energy gets subsidies because it is clean energy, so should nuclear. “Why are we taking down nuclear plants and leaving coal plants on line? This is completely ridiculous,” he said.

If the fossil energy lobby wins, the most vulnerable people — children, the elderly, and the ill — will pay the heaviest price.

Already, more people die prematurely from particulate matter pollution in Ohio than in any other state, according to the best-available science done by a team of researchers from MIT.

When particulates are inhaled, they can cause serious damage to the lungs and heart.

And the prevalence of asthma has actually increased in westernized countries including the U.S., in part due to particulate matter. And the science is clear that particulate matter increases childhood asthma attacks.

Ohio also has the third highest death rate (deaths per population). But if Big Oil gets its way, Ohio's nuclear plants will close and Ohio could become number one in death rate, as well as in death toll.

In a report for legislators, Big Oil’s lobbyists admit that closing Ohio’s nuclear plants will increase pollution, but claim it won’t violate the Clean Air Act.

The trick is that they focus on the least harmful pollutant — nitrous oxide — and ignore all the other pollutants, including particulate matter.

And if you read the fine print, Big Oil admits that ozone pollution will increase in Cincinnati and in communities near coal plants.

What makes Big Oil's attack particularly galling is that the oil and gas industry benefitted from large government subsidies for decades. Between 1978 and 2007, the Energy Department spent $24 billion on fossil energy research that led to the fracking revolution.

I was part of the team that discovered government support for fracking, and our research has been extensively reported and validated by the New York Times, Associated Press and a powerful new book by Foreign Affairs editor, Jonathan Tepperman called The Fix. Our full investigation can be read here.

Natural gas is environmentally positive when it replaces coal, but it's environmentally negative when it replaces nuclear plants.

And even if Ohio's nuclear plants were entirely replaced with natural gas, the result will be that other coal plants in Ohio and neighboring states will stay on-line longer, resulting in more premature deaths.

The problem isn't just that Big Oil is being greedy. The problem is that its greed comes at the cost of human lives.

Big Oil is trying to kill clean energy in Ohio and Pennsylvania. Here's who will pay the price.