While President Obama promotes health care legislation in Iowa today, polls taken since the bill passed find somewhat more support for the measure, but also reveal a nation still skeptical of overhauling the health care system.

Voters disapproved of the bill, 49 percent to 40 percent, in a Quinnipiac University poll taken this week after the House vote on Sunday. Just before the measure passed, a poll showed that opponents outnumbered supporters by 18 points, or 54 percent to 36 percent.

Similarly, a CBS News poll taken before the vote found respondents disapproving of the bill by 48 percent to 37 percent. That gap closed to 46 percent to 42 percent opposed when those respondents were reinterviewed after the vote.

Both polls also find Mr. Obama receiving better marks for his handling of health care since the bill passed, but his rating on the issue is still below 50 percent.

And in the CBS News poll, while most of those reinterviewed after the vote still said they disapproved of how the Democrats in Congress were handling health care, the sentiment appeared to be dropping. It was down 10 points, from 66 percent to 56 percent disapproval. (For Republicans, the change in the public’s disapproval was smaller — 63 percent now say they disapprove, compared with 67 percent before the vote.)

At the same time, the Quinnipiac poll reveals that none of the major players in Washington have emerged from this debate unscathed. Voters in the poll said they were more apt to think less favorably of Mr. Obama, the Democrats and the Republicans because of their handling of health care, rather than viewing any of them more favorably.

The CBS News poll further underscores the notion that Mr. Obama has yet to make the case for his health care agenda to most Americans. A majority of those reinterviewed still say they do not have a clear understanding of how the bill will affect them.

Passage of the legislation made no difference in the public’s opinion of whether the changes would improve the health care system over the next few years; just 3 in 10 continue to believe the changes will make it better.

Still, the CBS News poll finds a little more than half — 52 percent — see the new law as a major accomplishment for Mr. Obama’s presidency. About half call it a major accomplishment for the Democratic party.

Looking ahead, most in the CBS News poll say Congressional Republicans should continue to challenge parts of the bill. But 51 percent in the Quinnipiac poll disagree with moves by attorneys general in several states who are suing to try to block the changes from taking effect.

The Quinnipiac University poll was conducted March 22-23 among 1,552 registered voters nationwide and has a margin of sampling error of plus or minus 2 percentage points. The CBS News poll was conducted March 22-23 among 649 adults who were first interviewed by CBS News March 18-21. The margin of sampling error is plus or minus 4 percentage points.

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