Kathleen Sebelius, the health and human services secretary closely associated with the health care law, is stepping down. Democrats say it's a sign that the biggest problems are past, but Senate Republicans vow to use her successor's confirmation hearings as another forum for criticizing the law.
Democrats hardest hit by anti-Obamacare ads — including Sens. Kay Hagan of North Carolina and Mark Pryor of Arkansas — continue to defend the health law when asked, but they generally focus on other topics, campaign aides say.
Polls don't suggest public sentiment is shifting toward Democrats, said Robert Blendon, a professor of health policy and political analysis at the Harvard School of Public Health. But with at least 7.5 million people enrolled despite last fall's disastrous rollout of insurance markets, Blendon said, Democrats have some strong new material to use.
"Each of the Democratic candidates is going to have to make a calculation on whether or not they can motivate Democrats," Blendon said. "For Democrats to get an advantage out of the law, they have to convince people they have something to lose if the Senate changes hands."
Republicans need to gain six seats to control the 100-member Senate.
New political problems might arise for the health care law before the Nov. 4 election. For instance, the individual requirement to carry health insurance remains generally unpopular, and now penalties may apply to millions of people who remain uninsured.
So far, Republicans have had an edge in public opinion, particularly when those with strong sentiments about the law are considered. A recent AP-GfK poll found that strong opponents outnumber strong supporters, 31 percent to 13 percent. And motivated voters often make the difference in low-turnout nonpresidential elections. But the poll also found that most Americans expect the health law to be changed, not repealed.
That puts Republicans in a tricky situation: GOP primary voters demand repeal, but general election voters in November are looking for fixes.
"It's not a cheap and easy political target anymore," Laszewski said. "Republicans are going to have to tell us what they would do different."
Democrats deride GOP proposals to "replace" the 2010 health care law, saying they collapse under close scrutiny. Since they generally contemplate a smaller federal government role, many of the GOP ideas are likely to leave more people uninsured. Some approaches do not completely prohibit insurers from turning away people with pre-existing medical conditions.
Economist Douglas Holtz-Eakin, who advises many top Republicans, said the emerging GOP plans aren't tied to the ups and downs of Obama's law but look ahead to the 2016 presidential election, when the party will need alternatives.
Ultimately, he said, "there can't be a Republican 'replace.' ... There needs to be a bipartisan reform." That doesn't seem likely, but Holtz-Eakin said it was the only kind of change that will prove durable.
Democrats can cheer the latest statistics, "but they are not out of the woods yet," he said. "They have waived and deferred a million things they knew were unpopular, and those are still out there."
AP Director of Polling Jennifer Agiesta contributed to this report.
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