The health care reform plan working its way through the U.S. Senate now includes a proposal that requires young and healthy Americans to either buy health insurance or pay a $750 annual penalty for not having it.

But a new Rasmussen Reports national telephone survey shows that 55% of U.S. voters oppose that proposal. Just 32% of voters think young and healthy Americans should be forced to purchase health insurance or else pay a penalty. Fourteen percent (14%) are not sure.

Among voters ages 18 to 29, 29% favor the provision, known as “the individual mandate,” while 57% are opposed to it.

(Want a free daily e-mail update? If it's in the news, it's in our polls). Rasmussen Reports updates are also available on Twitter or Facebook.

Sixty-one percent (61%) of men oppose the enforced health insurance proposal, compared to 50% of women. African-American voters are nearly twice as likely as whites to support it.

As on many questions related to the contentious health care debate, there is a noticeable partisan divide. Seventy-seven percent (77%) of Republicans and 59% of voters not affiliated with either major political party oppose requiring young and healthy Americans to either buy health insurance or pay an annual penalty. Among Democrats, on the other hand, 46% think the provision is a good idea, while 33% oppose it.

Millions of young people historically have chosen to avoid the cost of health insurance by gambling on their general good health at that age. The individual mandate is intended to push them into buying health insurance.

In a survey in May, 31% of Americans said even those who are young and healthy should be required to buy health coverage. Fifty-six percent (56%) disagreed, saying if someone doesn’t want to buy insurance, they shouldn't have to.

While most voters oppose the “individual mandate” amendment to the health care plan, 59% favor putting a provision in the plan that would prohibit any new taxes, fees or penalties on families who make less than $250,000 a year.

The Senate Finance Committee added the “individual mandate” to its version of the health care plan on a bipartisan vote late last week, after the level of the penalty was reduced. But a Republican amendment to prohibit new taxes on those earning less than $250,000 was defeated on a party-line vote, with just one Democratic senator in favor of it.

Forty-six percent (46%) of voters now favor the health care reform plan, up five points from a week ago, but 50% are still opposed to it. With the exception of “bounces” following a couple of nationally televised presidential appearances, this is the first time support for the congressional health care effort has risen. Rasmussen Reports is tracking support for the plan on a weekly basis.

Sixty-one percent (61%) say it’s important for Congress to pass health care reform this year, but most would prefer a series of smaller reforms rather than a comprehensive approach. Sixty-three percent (63%) of voters say guaranteeing that no one is forced to change their health insurance coverage is a higher priority than giving consumers the choice of a "public option" health insurance company.

But right now 53% of those with health insurance say the proposed health care plan will force them to change their coverage.

Please sign up for the Rasmussen Reports daily e-mail update (it’s free) or follow us on Twitter or Facebook. Let us keep you up to date with the latest public opinion news.

See survey questions and toplines. Crosstabs and are available to Premium Members.