As House Democratic leaders unveiled the bill, their Senate counterparts await estimates from CBO on the finalized bill.
Senate Majority Leader Harry Reid, D-Nev., said earlier this week the Senate legislation will include a public option plan, but he did not divulge any more details.
The House Democrats' bill does include a public option, but it is not the Medicare-like public option that Pelosi wanted. The government-run insurance company created by the proposed bill would negotiate payment rates with health care providers just like private insurance companies. Pelosi simply could not get the votes to pass the "robust" version she preferred.
White House officials said today they have yet to evaluate the legislation, and defended the public option as a plan that would drive down costs, not increase them.
"You've seen people say that this is going to drive policies up in price. I don't think that -- I think whenever you're adding more choices through greater competition into the health care system, you're driving down costs," White House spokesman Robert Gibbs told reporters. "That's what the president wants to see. That's a big aim in health care reform, and I think that's what we're working toward."
The House Democrats' bill also creates a health insurance exchange whereby those who do not get insured through their employers can shop for coverage.
The House bill would require nearly all Americans to sign up for health coverage by 2013, either through their employer, a government program or the new exchange.
There is also an individual mandate requiring all Americans to have health insurance, although the penalties for non-compliance are lower than penalties in the Senate bill, which imposes a maximum fine of $1,500 for families who forgo insurance.
The House bill also includes an employer mandate. Companies who don't offer health insurance will be slapped with a fine, but small businesses are exempt.
The bill will be paid for, in part, with a 5.4 percent surtax imposed on those with incomes over $500,000 for individuals, $1 million for families. This tax increase is likely to be a key point of contention between Democrats, as the Senate version doesn't include this tax.
The House bill contains a long list of insurance reforms, including banning denial of coverage for pre-existing conditions, mandating wellness and prevention coverage, capping out of pocket expenses and prohibiting caps on benefits.
As Pelosi spoke, demonstrators tried to interrupt her remarks, but they were moved quickly by police.
ABC News' Dean Norland contributed to this report.