President Obama was more direct and explicit about his positions on environmental issues Tuesday night than in last year's State of the Union address, mentioning climate change by name and expounding on the need for environmental regulations.

Observers saw a new willingness on the president's part to talk about his stance on environmental issues, which have come under repeated attack by congressional Republicans, especially since they took control of the House in January of last year.

"I think that is a sign that he feels a little bit bolder," said Bill Schneider, a political analyst and resident fellow at the centrist Democratic think tank Third Way.

Part of the reason for this shift might be the sinking approval numbers of congressional Republicans. A United Technologies/National Journal poll conducted last week found that more voters trusted Obama to find solutions to the economic crisis than congressional Republicans by a margin of 41 percent to 29 percent.

"What we've seen for a couple months really is very, very gradually improving ratings for the president, and sharply deteriorating ratings for Congress and even more so for the Republican leaders of Congress," Schneider said.

The party's image was particularly harmed when Republicans on both sides of Capitol Hill moved to block an extension of Social Security payroll tax cuts late last year, he said.

Norman Ornstein, a resident scholar at the American Enterprise Institute and veteran observer of Congress, said political dynamics had shifted in Obama's favor -- at least for now. GOP congressional leaders have "bumbled" in Congress in the past few months, in particular on the payroll tax bill, he said. Their presidential hopefuls have managed to make the party look "ridiculous and extreme."

And at the same time, Obama appears to have given up trying to look like he is above the political fray in Washington and has instead embraced a more combative posture. Ornstein said this move had strengthened the president's image with voters frustrated with Washington's inaction on important issues like the economy.

"It's like a parent with unruly children in a restaurant who keeps trying to get them to be reasonable," he said. "The other patrons in the restaurant don't say, 'Boy, we're going to give you real points for trying to be reasonable, even if they're ruining our meal.'"

All these things may have combined to allow Obama to say words like "climate change" in his most important speech of the year, even as he did not say "war on terror."

Democratic media consultant Mark Longabaugh, a former political director at the League of Conservation Voters, said this was significant.

"Anything that gets in the president's State of the Union speech is meaningful," he said. "That's a huge, huge speech, and things don't get into it by accident."

The president's reference to climate change was brief.

"The differences in this chamber may be too deep right now to pass a comprehensive plan to fight climate change," he said.

But Obama managed to convey that he still wanted to see a carbon dioxide bill become law and believed that a time may come when that will be possible.

Manik Roy, vice president for strategic outreach at the Center for Climate and Energy Solutions, said that the one-sentence reference made it clear that curbing carbon dioxide remains an objective for the president.

Many environmentalists have criticized Obama for dropping climate change almost entirely from his public statements in the past year or two and replacing it with euphemisms about protecting public health.

"Being silent on this issue hasn't helped," Roy said. "Talking about it -- even if briefly -- is important."

Longabaugh also applauded Obama for this new boldness.

"I think it's very clear that the president is going to be more aggressive in taking on his opponents in the Congress," he said. "I think he's come to the conclusion that it's very hard to work with them and that he's going to rally public opinion to try to push through his agenda."

Eric Pooley, senior vice president of strategy and communications for the Environmental Defense Fund, said that polls show the public has embraced an agenda of clean energy and carbon mitigation.

"The president knows that there's no shirking from that battle, and his opponents have made it clear that they're going to campaign on it," he said. He noted that Obama and his would-be challengers are already facing off in ads and speeches over the administration's choice to grant a loan guarantee to now-bankrupt solar technology company Solyndra. Obama made reference to Solyndra -- and his support for clean energy -- in the State of the Union speech, though he did not use the company's name.

"It's going to be a debate," Pooley said. "And there are well-drawn positions here. And I can only conclude from what the president had to say that he thinks he has a strong argument. And I would agree with him."

But Schneider said that voters only really care about one thing right now: job creation.

"At a time when the No. 1 issue is jobs, the environment is always secondary," he said. "And that's the case right now."

The president can "nudge" other priorities along this year, Schneider said, but not at the expense of employment and economic growth.

"That is the national crisis right now," he said. "Not the environment, not climate change, not even the debt or the deficit. It's jobs, jobs, jobs."

Schneider and Ornstein both said that if the U.S. economy hits another major bump in the road in 2012, voters will hold Obama responsible for it and not Republicans in Congress.

Ornstein said he doubted that Obama's slightly higher approval numbers would lead the president to advance more ambitious environmental regulations in an election year.

"My guess is you're not going to see this year be a year in which the EPA moves much more sharply to a confrontational style," he said. "I think it's going to be a few changes here and there, some calibration, but an expectation that in a second term -- that's when you can begin to use your executive power in that fashion a little bit more."