WASHINGTON » If passage of the financial regulatory overhaul on Thursday proves anything about President Barack Obama, it is this: He knows how to push big bills through a balky Congress.

But Obama’s legislative success poses a paradox: While he may be winning on Capitol Hill, he is losing with voters at a time of economic distress, and soon may be forced to scale back his ambitions.

The financial regulatory bill is the final piece of a legislative hat trick that also included the stimulus bill and the landmark new health care law. Over the last 18 months, Obama and the Democratic Congress have made considerable inroads in passing what could be the most ambitious agenda in decades.

Obama has done what he promised when he ran for office in 2008: He has used government as an instrument to try to narrow the gaps between the haves and the have-nots. He has injected $787 billion in tax dollars into the economy, provided health coverage to 32 million uninsured and now, reordered the relationship among Washington, Wall Street, investors and consumers.

But as he has done so, the political context has changed around him. Today, with unemployment remaining persistently near double digits despite the scale of the stimulus program and the BP oil spill having raised questions about his administration’s competence, Obama’s signature legislation is providing ammunition to conservatives who argue that government is the problem, not the solution.

What Obama and his allies portray as progressive, activist government has been framed by his opponents as overreaching and profligate when it comes to the economy.

Even before the November elections, the White House is being forced to recalibrate. This week, Obama and Senate Democrats decided to press ahead with a scaled-back energy bill, having concluded after months of gridlock that the sweeping measure they once envisioned simply would not pass. It is a tactic that the president will likely have to employ more and more after the November elections, when Democrats will almost certainly lose seats — and may even lose control of the House or Senate.

"They clearly made a decision that political capital was something that should be used, not saved," said Steven Elmendorf, a Democratic lobbyist who worked for years as a senior leadership aide on Capitol Hill. "The reality is, he talked before the election about what he wanted to do, and he’s done it. He didn’t trim his sails, he didn’t change his philosophy. He didn’t compromise. The test will come in the fall: Can he and Democrats in Congress make the case to the American people that what he did was the right thing to do?"

That is a difficult case to make, though Obama is trying. The latest CBS News poll found that while a majority of Americans supported increasing regulations on banks and financial institutions, nearly three-quarters said Obama’s stimulus bill had not improved the economy, and only a little more than a third approved of the health care law.

"You know, sometimes these pundits, they can’t figure me out," the president said last week, campaigning in Kansas City, Mo., for the Democratic Senate candidate there. "They say, ‘Well, why is he doing that?’ That doesn’t poll well. Well, I’ve got my own pollsters, I know it doesn’t poll well. But it’s the right thing to do for America."

It is an argument that sounds eerily similar to the one Obama’s predecessor, George W. Bush, made to justify an unpopular war in Iraq as he watched his own poll numbers sink lower. Bush and his aides often felt they could not catch a break; when the economy was humming along — or at least seemed to be humming along — the Bush White House never got credit for it, because the public was so upset about the war.

In Obama’s case, people are up in arms over the economy. Just 40 percent of Americans now approve of Obama’s handling of the economy, the CBS News poll found. More than half said he was spending too little time on the economy. In one of the most striking findings, nearly two-thirds said the president’s economic policies had no effect on them personally — just 13 percent said they had helped them.

"Voters don’t have a checklist that they tick off, of what an elected official promised and then delivered," said Charlie Cook, the editor of The Cook Political Report, a nonpartisan newsletter that tracks congressional races. "They were enormously frustrated last year by the fixation on health care when they wanted a focus on the economy, with Democrats losing the messaging fight on whether what they did was right and effective or not."

Part of the problem for Obama is that he came to Washington vowing to change the partisan tone in the capital, something he has thus far been unable to do. Just three Senate Republicans voted for the financial regulatory bill on Thursday, continuing a pattern that began early in Obama’s presidency when just three Republicans joined him on the stimulus bill.

At this point, relations between the president and the opposing party are no better than they were when Bush left office. Within hours of the bill’s passage on Thursday, Democrats including Obama were reminding voters that the House Republican leader, Rep. John Boehner of Ohio, had called for its repeal. As Obama traveled to Michigan on Thursday to promote his economic policies, Boehner accused him of "a bunch of fuzzy math."

If Republicans reclaim control of the House, the Senate or both, Obama will find himself in a situation similar to that of the last Democratic president, Bill Clinton, who lost control of the House in 1994 in a historic realignment. Clinton responded by steering toward the center, searching for issues on which he could find Republicans to cooperate.

If Obama’s new tack on the energy bill is any guide, he may be willing to refashion himself as a pragmatist who will compromise in exchange for smaller victories. The coming elections may answer the question of how far the president, having had a taste of big things, is willing to bend.

"It could be a prescription for real gridlock, or it could be a prescription for great compromise," said John Feehery, a Republican strategist, "and I don’t think we know the answer."