As President Obama prepares for a major speech on Wednesday to relaunch his health care reform initiative, polling data continues to show that many Americans remain skeptical of the details.

Despite assurances from the president and congressional Democrats who authored the bill that no one with insurance will be forced to change their current coverage, 52% of those with insurance say it’s likely they will have to change coverage following passage of the congressional health care reform proposal.

A new Rasmussen Reports national telephone survey finds that 41% say it’s not likely that they will have to switch.

Perhaps the most frustrating aspect of the data for the president’s team is that the numbers have barely budged since the debate begin in June. This particular issue is especially significant since the overwhelming majority of Americans currently have insurance and tend to rate their own coverage in positive terms. A recent Wall Street Journal article by Scott Rasmussen noted that the “most important fundamental” in the health care debate is the fact that that 68% of American voters not only have health insurance coverage but rate their coverage as good or excellent. These voters enter the debate perceiving that they have more to lose than to gain.

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The current numbers include 31% who say it is Very Likely that they would be forced to change their coverage while only 18% say it’s Not at All Likely. Most Republicans and unaffiliated voters say it’s likely they would have to change plans. Thirty-nine percent (39%) of those in the president’s party agree.

That’s part of the reason that just 43% of all voters currently favor the president’s plan and 53% are opposed. Those who oppose the plan feel more strongly about it than those who favor it.

Numbers like these explain why the White House feels it’s necessary regain control of the health care debate. On most of the basic questions about the proposed legislation, skeptics outnumber the believers. Eighty percent (80%) say it’s likely that middle class taxes will go up if the congressional plan is passed. Two-thirds (68%) say that passage of health care reform will increase the deficit. Half believe the plan will increase costs and reduce the quality of care.

The president’s ability to convince voters will be put to the test on Wednesday night. He makes the speech at a time when his job approval ratings have stabilized after falling in July and August. Just 60% now say the president is at least as ethical as most politicians.

Perhaps the most challenging factor for the president is that 51% of voters think they have a good understanding of the proposed legislation. Just 47% say the same about the president, and only 22% believe Congress understands it that well. That’s one reason voters believe that the primary purpose of town hall meetings on health care should be for members of Congress to listen rather than speak.

Rasmussen Reports has been tracking support for the health care proposals on a regular basis since June. Beginning tonight (Tuesday), we will track support daily for several days to measure the response to the president’s speech.

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