President Obama, in his weekly radio address, beseeched voters to get behind his climate change plan and punish politicians who don't.

He may want to be careful what he asks for. Several of those lawmakers come from the president's own party.

Coal-state Democrats have been as scathing as any Republican in reaction to the president's plan, unveiled Tuesday in a speech at Georgetown University. The pushback was almost immediate, and a glaring signal of the trouble Obama may encounter as he charges ahead with new restrictions on coal-fired power plants.

Though Obama technically is going around Congress by having the Environmental Protection Agency impose the rules, moderate Democrats made clear they will pressure the administration from inside the party to scale back. They carry a simple message: The regulations will kill jobs, but working with the coal industry to improve its own clean-coal technology won't.

West Virginia Democratic Sen. Joe Manchin, calling the president's plan a "war on America," delivered one of the most forceful rebuttals in an interview with Fox News.

"It's just ridiculous. ... I should not have to be sitting here as a U.S. senator, fighting my own president and fighting my own government," he told Fox News. "I will continue to reach out, but I need a partner here. I don't need an adversary."

Manchin argued that the coal industry has the technology to reduce emissions. But he said the government, rather than work with the industry, is setting unattainable standards.

The cornerstone of Obama's plan was a call for the first-ever regulations on emissions for existing power plants.

"Why is this economy going to be taking this hit? Why are jobs going to be lost, and they will be lost," Manchin said.

North Dakota Democratic Sen. Heidi Heitkamp echoed the remarks, backing the overall intent of addressing climate change but accusing Obama of amplifying the "war on coal" with regulations that "choke off good-paying American jobs."

She, too, said the government should encourage investments in technologies that cut emissions with clean-coal technology.

Advocates of the industry argue that it has made strides toward making coal more environmentally friendly. According to the American Coalition for Clean Coal Electricity (ACCCE), 10 clean-coal technology plants have launched since 2011. Another five are under development or scheduled to come online.

But the industry claims to be struggling to both make those investments and meet the demands of federal regulations. Group President Robert M. "Mike" Duncan says EPA regulations have played a big role in the closure of nearly 290 coal plants so far this year.

Initially, there's very little the industry and skeptical lawmakers can do about the new EPA rules. But Congress could try to block the agency's effort with legislation. The rules could face legal challenges. Plus, the EPA will have to work with the states to implement whatever regulations it creates.

Obama said Tuesday that he anticipated claims that the rules will "kill jobs," but compared those warnings to those throughout history whenever the federal government tried to act on the environment.

"The problem with all these tired excuses for inaction is that it suggests a fundamental lack of faith in American business and American ingenuity," he said.

Obama said he's willing to work with lawmakers but said: "I don't have much patience for anyone who denies that this challenge is real. We don't have time for a meeting of the flat-earth society."

He underscored that point in Saturday's radio address.

Urging voters to act, he said: "Educate your classmates and colleagues, your family and friends. Speak up in your communities. Remind everyone who represents you, at every level of government, that there is no contradiction between a sound environment and a strong economy -- and that sheltering future generations against the ravages of climate change is a prerequisite for your vote."

Reaction from Democrats has spanned the gamut.

Manchin's West Virginia colleague, Democratic Rep. Nick Rahall, called the president's plan "misguided, misinformed and untenable."

But the state's other Democratic senator, Jay Rockefeller, took a middle-of-the-road position, saying the president needs to provide more information about how miners would be affected.

And in Kentucky, Democratic Rep. John Yarmuth issued an unequivocal endorsement, saying the new standards would "address the devastating health, environmental, and economic consequences of climate change."