Updated: 3:12 p.m.

AARP, the nation’s largest senior citizens organization and a key stakeholder in the health care debate, on Thursday endorsed the House’s reform bill.

At a press conference Thursday morning, AARP CEO Barry Rand issued a statement saying his group believes the House’s measure would make coverage affordable to its younger members while at the same time protect Medicare benefits for older seniors.

“We’ve read the Affordable Health Choices for America Act and we can say with confidence that it meets those goals with improved benefits for people in Medicare and needed health insurance market reforms to help ensure every American can purchase affordable health coverage,— Rand said in a prepared statement.

AARP said this marks the first time the organization has put its weight behind a comprehensive health care reform package. AARP officials said they would throw their organization’s considerable resources, which include advertising, behind pushing the House bill.

“We will be using all of our resources in the coming hours as the House deliberates,— said Nancy LeaMond, AARP executive vice president. She added that the organization had sent e-mails to 4 million of its activists alerting them to the endorsement.

Rand said AARP was not worried about angry members canceling their membership because of the endorsement. He said the group had weathered controversies before that prompted members to leave such as when AARP criticized then-President George W. Bush’s plan to create private Social Security accounts.

The group, meanwhile, has sent a letter to Speaker Nancy Pelosi (D-Calif.) to let her know of AARP’s backing. In the letter to Pelosi, Rand urged the House to further improve the bill. He said the organization was troubled by provisions that give brand name drug companies 12 years to develop biologic drugs before cheaper generic versions are allowed. Rand also said AARP wanted the bill to include funding for Medicare, graduate nursing education and improvements in access to Medicaid home and community-based services. Both areas are covered in the Senate Finance Committee’s health care reform bill.

The support of the influential seniors group, with its multimillion-dollar lobbying budget, should provide a boost for Democratic leaders as they seek to rally support for the plan.

While the AARP has generally been supportive of health care reform, it has until now been reluctant to back specific details in the plans being crafted in the House and Senate.

Republicans, meanwhile, have criticized the group, saying the seniors lobby is backing health care reform efforts that would make certain private Medicare plans more expensive to seniors. Republicans have also attacked the AARP for being in partnership with private health coverage plans, which GOP lawmakers claim will benefit if the Democratic plans are approved.

Of course, it was the Democrats who were upset with AARP when the group backed a 2003 GOP effort to provide prescription drug coverage to Medicare recipients.

Meanwhile, another significant player in the health care reform debate, the American Medical Association, reiterated its support for the House bill during a meeting in Houston on Thursday.

“The Affordable Health Care for America Act is consistent with our principles of pluralism, freedom of choice, freedom of physician practice and universal access,— AMA President J. James Rohack said in a statement.

The AMA was an early supporter of the House efforts, writing a letter in July to Ways and Means Chairman Charlie Rangel (D-N.Y.) lauding the health care legislation the committee had approved.

While the AMA has long been a well-financed advocate in Washington, D.C., its clout may be diminishing. The group was unable to persuade the Senate recently to approve a $245 billion bill that would adjust physician reimbursement rates under Medicare.

Nevertheless, President Barack Obama Thursday touted the support for the bill by both the doctors and the AARP as a big boost to his health care initiative. He said the AARP’s support would help counter critics, including insurance companies, which have complained the health care bills, as drafted, would result in higher costs to consumers.

At a press conference, Obama said people should remember the AARP endorsement “the next time you see a bunch of misleading ads on television.—

Obama also said the AMA membership “are men and women who know our health care system best and have been watching this debate closely. They would not be supporting it if they really believed that it would lead to government bureaucrats making decisions that are best left to doctors.—