The American Cancer Society Cancer Action Network, the advocacy arm of the American Cancer Society, also threw its weight behind the House Democrats bill, saying it will improve health care for cancer patients and their families.
But the support from these influential organizations did little to tame the "tea party" protestors who gathered on Capitol Hill Thursday.
Chanting "Kill the Bill," they rallied outside the Capitol building and then some converged outside Pelosi's office, littering the hallway with torn copies of the 1,990-page House bill.
"The Democrats do not have the American people and their best interest at heart," Linda Giresi, who came from Union, N.J., told ABC News. "They have their own self interests at heart. And that is the root of this 2,000 page outrage."
Meanwhile, the Senate leadership has been rather quiet on their version of health care overhaul legislation, which has yet to be scored by Congressional Budget Office.
Senate Majority Leader Harry Reid, D-Nev., has been mum on the contents of the bill, except to say it does include a public option plan. Unlike the House bill, however, the Senate plan gives states the option to opt out of a government-run insurance plan. Reid is still waiting for the Congressional Budget Office to come up with an estimated cost of several possible variations of his bill before deciding which one to introduce in the Senate.
House Democrats say their legislation would insure 36 million more people in the next 10 years, covering 96 percent of all Americans. That is more than the Senate bill, which would cover an estimated 29 million additional people.
The House bill would also expand Medicaid coverage and provide more support to low-income citizens.
House Democratic leaders argue that it would not add a dime to the deficit, an important factor considering President Obama has said he will not sign any legislation which does so.
Despite Pelosi's push to get health care legislation passed in the House, and the White House's confidence that it will get done by the year's end, senior Congressional Democrats have indicated that it is highly unlikely that a reform bill will be completed this year.