WASHINGTON - The overwhelming majority of Americans support substantial changes to the country's health care system, including a government-run health insurance option, a new opinion poll found.

The survey by The New York Times and CBS News also indicated most Americans would be willing to pay higher taxes so everyone could have health insurance.

Eighty-five percent of respondents said the health care system needed to be fundamentally changed or completely rebuilt, according to the poll.

In addition, the survey found that 72 percent of those questioned supported a government-administered insurance plan -- something like Medicare for those under 65 -- that would compete for customers with private insurers.

Twenty percent said they were opposed.

When asked which party was more likely to improve health care, 18 percent of said the Republicans while 57 percent picked the Democrats. Even one of four Republicans said the Democrats would do better.

However, half of those who identified themselves as Republicans said they would support a public plan, along with nearly three-fourths of independents and almost nine in 10 Democrats, according to the poll.

President Barack Obama wants Congress to approve his health care reform proposals by the end of the year in order to fulfill one of his key campaign promises -- providing health care to the 46 million Americans, some 15 percent of the population, who currently do not have any medical coverage.

Obama's health care plan includes a government insurance option, which has been fiercely criticized by Republicans.

At the same time, the survey found that 77 percent of Americans were very or somewhat satisfied with the quality of their own health care, a factor that is being exploited by opponents of the president's proposal.

The poll of 895 adults was conducted from June 12 to 16 and had a margin of sampling error of plus or minus three percentage points.