WASHINGTON » With the first enrollment deadline now passed, Republicans who have made the repeal of President Barack Obama’s health care law their central aim are confronting a new reality: More than 2 million Americans are expected to be getting their health insurance through the Affordable Care Act come Jan. 1.

The enrollment figures may be well short of what the Obama administration had hoped for. But the fact that a significant number of Americans are now benefiting from the program is resulting in a subtle shift among Republicans.

"It’s no longer just a piece of paper that you can repeal and it goes away," said Sen. Ron Johnson, R-Wis., a Tea Party favorite. "There’s something there. We have to recognize that reality. We have to deal with the people that are currently covered under Obamacare."

And that underscores a central fact of U.S. politics since Franklin D. Roosevelt signed the Social Security Act during the Depression: Once a benefit has been bestowed, it is nearly impossible to take it away.

Republicans are considering several ideas for how to proceed. Johnson argued that Congress should do away with the mandate that most people obtain insurance, but not the online exchanges at the heart of the law. Instead, he said, the options in the marketplaces should be augmented by other choices that fall short of the law’s coverage standards, such as catastrophic health plans. (Many policy analysts and insurance companies say such a move would not work, because the mandates are essential to delivering a diverse pool of uninsured people.)

Sen. Lindsey Graham, R-S.C., said that health care strategy was the hottest topic of debate in closed-door political sessions.

"The hardest problem for us is what to do next," Graham said. "Should we just get out of the way and point out horror stories? Should we come up with a mini Contract With America on health care, or just say generally if you give us the Congress, the House and the Senate in 2014, here’s what we will do for you on multiple issues including health care? You become a more effective critic when you say, ‘Here’s what I’m for,’ and we’re not there yet. So there’s our struggle."

Sen. Kelly Ayotte, R-N.H., said she was teaming up with Democrats on a host of incremental changes to the law, such as expanding health savings accounts and repealing a tax on medical devices. And other Republicans are wondering aloud how long they can keep up the single-minded tactic of highlighting what is wrong with the law without saying what they would do about the problems it was supposed to address.

Rep. Tom Price, R-Ga., a physician and a prominent conservative voice on health care, is pushing what he calls the Empowering Patients First Act, which would repeal the health care law but keep its prohibition on exclusions for pre-existing conditions in private health insurance.

The bill would allow for insurance to be sold across state lines, push small businesses to pool together to buy insurance for their employees, expand tax-free health savings accounts, cap malpractice lawsuits, and offer tax credits of $2,163 for individuals and $5,799 for families to buy health plans.

The American Action Forum, a conservative advocacy group run by Douglas Holtz Eakin, a former director of the Congressional Budget Office, analyzed the Price plan this month. The group concluded that it would lower insurance premiums by as much as 19 percent by 2023, while leaving the ranks of the uninsured about 5 percentage points higher than the Affordable Care Act would by then.

Rep. Paul D. Ryan of Wisconsin, the Republican vice-presidential nominee in 2012 and a possible 2016 presidential hopeful, is preparing his own health insurance plan for release early next year.

Ryan’s plan will build on one that he and Sen. Tom Coburn, R-Okla., introduced in 2009, according to aides familiar with it. The proposal, called the Patients’ Choice Act, would have eliminated the tax break for employer-provided health care to finance a tax credit of about $5,700 for families and $2,300 for individuals. States would have been asked to create insurance marketplaces like the ones many have created under the Affordable Care Act.

As with the Obama health care law, the Ryan proposal demanded that insurers meet minimum standards of coverage and be prevented from excluding the sick. But instead of mandating penalties for failing to buy insurance, the approach would have automatically enrolled people unless they opted out.

Price said Thursday that he was "cautiously optimistic" that he, other lawmakers and House Republican leaders could meld the different approaches into one alternative health plan to take to voters — and possibly the House floor — in the 2014 election season.

"It’s the minority’s responsibility to provide a contrast," he said. "It’s important that we put forward an upbeat, positive proposal, so the American people know there is an alternative."

Whether voices like Ayotte’s or Johnson’s will prevail is unclear, given the deep opposition among rank-and-file Republicans. Graham said that Republicans would probably get away with denouncing the Affordable Care Act through the midterm elections, but that by 2016 they would need to have a fully formed alternative.

White House officials acknowledge that the administration needs to focus on making sure all those who enrolled in health plans actually have coverage Jan. 1. HealthCare.gov received 2 million site visits Monday, the official deadline for coverage starting Jan. 1, and the insurance call center took more than 250,000 calls, said Julie Bataille, a spokeswoman for the Department of Health and Human Services. More than 129,000 people left emails Monday after finding the website jammed with traffic, and activity remained brisk Tuesday for those taking advantage of a 24-hour extension.

"Millions of people visited the state and federal marketplaces this week to purchase private health plans," said a White House spokeswoman, Tara McGuinness. "The final tallies are being rounded up, but we believe the deadline encouraged decision-making for hundreds of thousands of families who will have access to care in the new year."

State-run exchanges had a similar crush. Almost 26,000 people signed up in New York state on the last enrollment day. California enrolled 27,000, and Washington state 20,000. Connecticut beat its expectations with 6,700 new sign-ups.

Some of those rushing to enroll are bound to find problems in January as private insurers struggle to line up federal and state website enrollment with actual policies, a White House official said. And attitudes toward the law are not going to change overnight.

But if Obama’s approval rating on health care is tepid, Congress’s is abysmal. Just 19 percent of Americans approve of the way congressional Republicans are handling health care. Still, a /CBS News poll this month showed that nearly two-thirds of Republicans wanted to have the Affordable Care Act repealed, and most Republican lawmakers are appealing to those constituents.

"A few million people are buying a product that has features they don’t want, paying more for it than they should have to pay for it because they had to buy it through this government-mandated mechanism," said Sen. Patrick J. Toomey, R-Pa. "I don’t think that changes anything fundamentally at all."

Asked what should be done with the millions of people getting health care through the law, Sen. Dan Coats, R-Ind., said, "Call the White House and ask them."

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