With the economy giving President Obama little to run on, the Democrats are shifting to a risky, partisan strategy to re-energize the party.

The president's emerging political stance is a sharp contrast to the soaring, inspirational rhetoric that made him a popular figure two years ago.

But the new tone reflects a grim political calculation by the White House -- that this year to win, they have to play small and dirty.

"The administration wants to make sure that whatever losses they suffer -- and they will suffer losses -- are within the normal range of a midterm election year," said Joe Tuman, a political scientist at San Francisco State University.

He added, "Any higher turnout this year is going to come from people not inclined to support Democrats."

Two new polls illustrate some of the challenges Obama is facing. A Pew Research poll last week found Republicans more fired up about the midterms than any off-year election since 1994.

Pew found 56 percent of Republicans more enthusiastic about voting this year than in previous elections -- a state of mind that could portend a high turnout advantage for the party.

A new Gallup poll found 43 percent of independent voters said they would support a Republican candidate this year, to 34 percent who said they would vote Democratic.

The so-called enthusiasm gap has White House strategists worried, and consequently moving Obama away from the populist rhetoric of the 2008 campaign toward a more pointed appeal to the party's base.

But while he is getting more overtly political, Obama is blending it with a message that laments the pettiness of politics in Washington.

"Before I was even inaugurated, there were leaders on the other side of the aisle who got together and they made the calculation that if Obama fails, then we win," the president said. "They figured 'If we just keep on saying no to everything and nothing gets done, then somehow people will forget who got us into this mess in the first place and we'll get more votes in November.' "

By writing off independents, Obama can take more latitude in directly criticizing Republicans, which he is doing more lately, to try to juice up his own party's flagging political enthusiasm.

"I think he has forgotten what kind of president he ran to be, which was bigger than partisanship and about big ideas," said Rep. Kevin Brady, a Texas Republican on the House Ways and Means Committee. "The way he is running now, it makes him look like a small president."

The White House strategy includes playing up Republican ties to the political villains of the day -- bankers and big oil -- combined with a message that Republicans don't care.

"What you see is a uniform strategy of battling for Wall Street, apologizing to BP, but turning a hard heart against those who are hit the hardest by this toughest economy since the 1930s," said Tim Kaine, chairman of the Democratic National Committee.

It's a tricky message -- since Obama is increasingly taking reluctant ownership of the moribund economy that has many people hurting.