The head of the Environmental Protection Agency appeared to hurl barbs at Congress on Tuesday, referring to an unnamed group of climate change "deniers" who aren't "normal" and who won't "carry the day" in a democracy.

EPA Administrator Gina McCarthy made the comments while addressing a climate change summit at the White House Tuesday to frame the effects of global warming on public health.

McCarthy said a report her agency released Monday makes the case for taking action against climate change by calculating the price Americans will pay for not taking action, including the thousands of lives lost due to global warming and the impact felt on the economy.

She said the EPA put out the report "not to push back against climate deniers," but to help "normal people" make a decision about the kind of world they and their children want to live in.

"I've batted my head against the wall too many times" trying to convince climate change deniers that global warming is occurring, she said. "You can have fun doing that if you want," but "if the science hasn't already changed their mind then it never will."

She said she is convinced that the climate deniers will not win in the campaign to address global warming. "In a normal democracy, it is not them that carries the day," McCarthy said. "It is normal human beings that haven't put their stake into politics above science."

"It's normal human beings that want us to do the right thing," she added. "And we will."

Her comments were being made around the same time Republican Sen. Shelley Moore Capito of West Virginia was holding a hearing on the harm the EPA's Clean Power Plan poses to energy producer states and small businesses. The EPA plan is the centerpiece of President Obama's plan to address climate change by curbing emissions from existing power plants.

"We are going to get our Clean Power Plan out. It is going to happen," McCarthy told those attending the summit, which included a broad range of public health advocates and environmentalists.

The climate summit follows another last week to announce $4 billion in private investment to develop renewable energy and other low-emission technologies. Observers say the summits are being used to push the issue of climate change ahead of the Clean Power Plan being issued in August.

Yet at the same time, the House is preparing to pass legislation as soon as Wednesday that would delay implementation of the plan. The House measure would give states the ability to opt out of the rules, while allowing them to forego compliance until judicial review has concluded.

In the Senate, Capito said that companion legislation she introduced in May continues to gain strength. Capito said she is "proud to have more than 30 cosponsors," including Majority Leader Mitch McConnell, R-Ky., and Energy and Public Works Committee Chairman James Inhofe, R-Okla.