"Let's seize reform, the need is great," Obama said at an appearance that had the feel of a campaign rally.
"How much higher do premiums have to rise before we do something about it?" said Obama, making the first in an expected string of out-of-town trips to pitch his plan to remake the health care system.
The president said dismissively that Republican critics in Congress contend they want to do something about rising health care costs but failed when they held power. "You had 10 years. What happened? What were you doing?" he said to applause from an audience at Arcadia University.
Obama made his appeal as Democratic leaders in Congress worked on a rescue plan for sweeping changes in health care that seemed earlier in the year to be on the brink of passage. The current two-step approach calls for the House to approve a Senate-passed bill despite opposition to several of its provisions, and for both houses to follow immediately with a companion measure that makes a series of changes.
The White House has said it wants the legislation wrapped up by March 18, but that seems unlikely. The companion bill has not yet been made public, and a protracted debate is expected in the Senate, where Republicans vow to resist even though they will not be able to block passage by filibustering.
Obama's stated goals across more than a year of struggle have been to extend coverage to millions who lack it, ban insurance industry practices such as denying coverage on the basis of pre-existing conditions and cut costs.
Republicans dismissed Obama's argument instantly. "The American people have heard all this rhetoric from the president before, and they continue to say loudly and clearly they do not want a massive government takeover of health care," said House Republican Leader John Boehner of Ohio, who added the president's plan was "heavy on snake oil."
Senator Arlen Specter, who travelled with Obama to the event in suburban Philadelphia, said the president's determined tone was "as fiery as I've seen him since the campaign." Specter told reporters that Obama is starting to rally votes for the legislation, and that the outcome is about more than health care.
"The bill is really a test now of whether Congress can govern," he said.
Obama has long identified the insurance industry as an obstacle to changes along the lines he seeks, but the administration's actions and rhetoric seem to have escalated in recent days.
The president's proposal would give the government the right to limit excessive premiums increases - a provision included after one firm announced a 39 percent increase in the price of individual policies sold in California. Kathleen Sebelius, the secretary of health and human services, convened a White House meeting with insurance executives last week, and followed up with a letter released in advance of Obama's speech.
It asks companies to "post on your web sites the justification for any individual or small group rate increases you have implemented or proposed in 2010."
In his remarks, Obama referred to a recent report from Goldman Sachs, the investment bank, saying that a lack of market competition makes it beneficial for insurers to drop customers or ignore new business and raise rates on remaining customers instead. Goldman's conclusions were based on a conference call with an industry expert at a major insurance broker.
Insurers have blamed rising rates on the growing prices of prescription drugs, hospital stays and other medical items.
The president's remarks came nearly a week after he took command of a final bid to pass his health care legislation and told a White House audience he wanted Congress to vote yes or no within a few weeks.
In the days since, he has met with two groups of wavering Democratic lawmakers, stressed the health care issue in his weekly radio and Internet address, and announced a trip to St. Louis for later in the week.
Full Democratic support is far from certain. Some party moderates are uneasy about the cost of the $1 trillion bill and its language on abortion, and some House Democrats are suspicious of whether their Senate colleagues would follow through on promises to work out the differences in the bills.
The Democratic plan includes greater consumer protections and a ban on discriminating against customers with pre-existing conditions. Small businesses also would receive a tax credit this year. The White House hopes the immediate changes created by the bill would give Democratic candidates a strong platform on which to campaign in the fall.
Though Obama has included some GOP proposals in his plan, Republicans have called for the existing bills to be scratched and for the process to start anew. Party leaders insist they're on the side of a public that doesn't want the government-controlled health care they maintain the president's plan would create.
