Republicans have launched an assault on AARP, which joins a growing list of groups supportive of the Democrats’ agenda that are being targeted by conservatives.

House Republicans on the Ways and Means Committee on Wednesday released a report that accuses the influential senior citizens organization of having a conflict of interest because it will financially benefit from the health care overhaul that the group heavily lobbied for last year. AARP collects royalties from endorsing health insurance policies and other products.

The report, which also notes the generous salary and travel benefits of AARP executives, questions the tax-exempt status of the organization; the Members are forwarding the report to the IRS for review.

“This is about whether this entity is misrepresenting itself to seniors,” said Rep. Charles Boustany (R-La.), chairman of the Ways and Means Subcommittee on Oversight. He was joined by Rep. Wally Herger (R-Calif.), chairman of the Ways and Means Subcommittee on Health, and Rep. Dave Reichert (R-Wash.) at a Capitol press conference to discuss the findings of the 18-month investigation. The Ways and Means panel will hold an oversight hearing Friday on AARP’s organizational structure and finances.

A GOP lobbyist suggested that the report is part of a pattern of House Republicans going after groups that worked against them on key legislation when they were out of power.

“There is certainly a sense of getting back at some of those groups that supported” health care reform, said Chris Lamond, a Republican lobbyist with Thorn Run Partners. “It is a little bit like, ‘We are in charge of the House side, we are going to hold their feet to the fire.’”

AARP officials disputed the Republicans’ contention that AARP’s policy decisions are driven by business interests.

“We are not an insurance company,” President Lee Hammond said. He noted that the 37-million-member group has opposed legislation supported by the insurance industry. Hammond also said the group had been in regular discussions with the IRS, which had not expressed any problem with the group’s tax-exempt status.

Drew Nannis, an AARP spokesman, said endorsing insurance products “meets an unmet need for our members.”

Lamond said he did not see a “master overall strategy” but added that the GOP majority wanted to signal to groups such as AARP that unlike last session, they have to pay attention to Republican concerns.

“The Republicans are playing political hardball — from state capitals to Washington,” said Thomas Mann, a political scholar at the Brookings Institution. “They are looking to weaken Democratic-leaning groups any way they can.”

Republican governors around the country, including in Wisconsin, Ohio and Indiana, have sought to curb collective bargaining rights and reduce dues-collecting abilities of public employee unions. In Washington, D.C., the GOP-controlled House voted to eliminate funding for entities perceived as liberal allies, such as Planned Parenthood and NPR.

In 2009, Republicans were successful in prodding Congress to deny federal funding to the housing and anti-poverty lobbying group the Association of Community Organizations for Reform Now after the release of a hidden-camera video by conservative activists who, posing as a prostitute and pimp, received housing and tax advice from ACORN workers.

Ron Pollack, the executive director of Families USA, a liberal health care advocacy group, interpreted the offensive against AARP as an effort to stifle groups that continue to back the implementation of health care reform.

“Perhaps they selected AARP under the assumption that if you can intimidate such as large organization, it will have a similar impact on smaller organizations,” Pollack said. He also speculated that by criticizing AARP, Republican leaders may be trying to appease their more conservative Members who may be frustrated that the new health care law has not been repealed.

Republican lawmakers said they are not targeting AARP to silence the supporters of the health care overhaul.

“This has nothing to do with trying to politicize the health care bill,” Reichert said. The lawmaker, who noted that his previous job was in law enforcement, said he was trying to ferret out what he suspected were questionable activities by the seniors group.

AARP has been one of the most formidable lobbying forces in Washington, with a substantial budget and the ability to activate a nationwide grass-roots network.

Last year, the group ranked among the top 10 lobbying spenders, shelling out more than $22 million.

In the fourth quarter alone, the group filed with Congress a 51-page lobbying report that included prodding lawmakers on issues including health care, financial reform, housing for the elderly and Social Security.

The group has also been one of the most powerful defenders of Social Security, the entitlement program that some Republicans are vowing to tackle in their bid to lower the deficit.

AARP was instrumental in killing President George W. Bush’s proposal to create private retirement accounts as part of Social Security reform.

By discrediting the seniors group, Republicans might be able to diffuse some of the opposition to an overhaul of the entitlement program.

But Jim Martin, the founder of 60 Plus Association, a conservative seniors organization, said he doubted the GOP assault would have much effect on AARP, which has survived criticism in the past.

“They are a behemoth,” he said. “It’s a one-day or two-day story. Then AARP goes on its merry way.”