WASHINGTON » After months of pummeling by Republicans and a grim election season approaching, Democrats on Tuesday had a rare bright day. President Barack Obama’s announcement that the new health care plan had enrolled 7.1 million Americans coincided with a the release by Rep. Paul Ryan of a new Republican budget that proposes changes in Medicare and deep cuts in spending.

It’s far too early to say a political turnaround is at hand, but for the first time this election year, Democrats are evincing some confidence that they have at least stanched the bleeding.

"It’s changing. If you’ve been around awhile, and I’ve been around awhile, you can sense it," said Sen. Richard J. Durbin of Illinois, the No. 2 Democrat in the Senate. "You’re not going to turn away seven or 10 million people from insurance coverage doesn’t work anymore. And then comes Ryan. Thank you, thank you congressman Paul Ryan, for reminding us what Republicans would do if they had control."

The Democrats’ newfound confidence may well be premature. Historically, a president’s approval ratings are the primary determinant of his party’s performance in a midterm election. On average, presidents below a 50-percent approval rating have lost an average of almost 40 House seats in midterms. And Obama’s ratings seemingly mired in the low to mid-40s may prove to be more tied to an economy that most Americans say is still in recession than to the health care law that may have turned a corner.

"Even though the Democrats are trying to take some victory lap, it’s very short term," said Sen. John Thune of South Dakota, chairman of the Senate Republican Conference. "The bad news continues. The hits keep coming."

But for the first time in a while, Democrats this week found themselves talking up a contrast between their agenda protecting the newly ensured, raising the minimum wage and renewing unemployment benefits and a Republican plan that would cut health care and education spending deeply, and move Medicare toward private insurance.

"The choice is very stark," Sen. Harry Reid, D-Nev., the majority leader, said Wednesday on the Capitol steps, flanked by more than 30 Democratic senators in a campaign-style rally. "The American people are watching."

And Republicans found themselves in a new position: On the defensive, justifying a budget that has already proven to be a political loser ("What’s the Democrats’ plan?" House Speaker John A. Boehner of Ohio asked Wednesday) and trying to explain what would happen to more than 10 million people who have signed up for insurance through the president’s health care law via a private plan or Medicaid and would be left at sea with its repeal.

"The president can go out there and tout all the people he’s signed up, but how about the young man I talked to last week out in California whose premiums have doubled? His co-pay and deductibles tripled, and his wife’s hours got cut to 29 hours," Boehner said. "My insurance premiums nearly doubled. My co-pays and deductibles tripled under Obamacare."

For Democrats, this spring at least should be a respite. With the closing of the Affordable Care Act’s first open enrollment period Tuesday, nothing much will happen to the law until after the election when the next enrollment period begins and employer-mandated coverage begins.

On the plus side, the president’s announcement that 7.1 million Americans had signed up for private health policies through the law’s exchange is likely to prove understated. Once totals are tabulated to include new Medicaid enrollees, people who signed up for new federally protected policies through private insurance brokers, and young adults who have stayed on their parents’ policies because of the law, the figure is likely to be at least double that.

Moreover, the Ryan budget, which is expected to pass the House Budget Committee on Wednesday night, will present the Democrats a chance to expand the political conversation beyond health care, to more Democratic-friendly terrain, like Medicare, Social Security, education funding and health research. The tax-and-spending plan once again proposes to convert Medicare into a "premium support" system where seniors would be given subsidies to purchase private insurance a proposal that Democrats ran against successfully in 2012.

It cuts Medicaid by $1.5 trillion over 10 years, food stamps by $125 billion, education programs by $145 billion including Pell grants and make university students begin paying interest on student loans while still in college.

Celinda Lake, a Democratic pollster, forecast that 57 percent of the electorate would be over 50 this November, compared with 43 percent in 2012.

"The ability to drive our advantage on Medicare will be invaluable," she said.

Republicans, for now, are not that worried. Their core voters remain more energized that the Democratic base, said Bill McInturff, a Republican pollster, and are likely to remain opposed to the health care law, regardless of the enrollment numbers.

"The health care law has always been characterized by stronger Republican opposition than Democratic support," he said. "It is possible that Democratic support for the law could increase, but fundamentally changing opinion of the law will be difficult in the short term."

But some Republican members of Congress are showing a newfound willingness to negotiate changes in the law rather than demanding its repeal. Last month, Reps. John Carney, D-Del., and Charlie Dent, R-Pa., wrote to Secretary of Health and Human Services Kathleen Sebelius requesting minor changes to Healthcare.gov to ease enrollment. Of the 75 signatories, 18 were Republicans, including hard-core opponents of the law, like Reps. Michele Bachmann of Minnesota, Rob Woodall of Georgia, Mick Mulvaney of South Carolina and Mark Meadows of North Carolina. That is a marked contrast from the position most Republicans once took, which was to do nothing to help constituents find insurance through the law.

"The law’s real. It’s there," said Rep. Reid Ribble, R-Wis., a signer of the letter. "You’re seeing a recognition that the law’s in place, and if our constituents are going to be penalized for it, the federal government ought to make it work."

© 2014 The New York Times Company