Rebuffed by the White House and largely ignored by Congressional Democrats, House and Senate Republicans are using a tax code change in President Barack Obama’s budget proposal to gin up opposition to the president’s plan among charities and nonprofits, a traditional bastion of Democratic support.

So far, however, few of the nation’s leading charitable organizations appear to be taking the bait, at least for now.

House Minority Leader John Boehner (R-Ohio) launched the effort with a letter to 10 nonprofit groups on March 6, asking that they send him their thoughts on a provision in the Obama budget that would cap itemized deductions for charitable donations at 28 percent to help pay for the administration’s $634 billion health reform fund.

“Included in the budget is a proposal to reduce the value of the charitable contributions deduction for certain taxpayers,— Boehner wrote. “I am concerned that this change will have a profound impact on organizations that rely on charitable contributions and solicit your input on the anticipated effect it may have on the ability of your organizations to deliver effective services to families all across the country.—

However, Boehner’s office has yet to hear back from any of the nonprofits.

Several contacted by Roll Call did not respond to inquiries about his overtures regarding the charitable tax deduction: Catholic Charities USA, Salvation Army, AmeriCares, World Vision and the American Heart Association.

The March of Dimes, American Cancer Society and the American Lung Association declined to comment. The YMCA of the USA had not received the letter at its main offices in D.C. or Chicago, a spokeswoman said.

A spokeswoman for the United Way of America said the group had not yet responded to Boehner’s letter but expressed concern that the provision could negatively affect its contributors and “active community investors.—

“We await the release of the House and Senate budget drafts so we can see how this issue is handled in those documents,— said Sal F. Fabens, public relations director for the group. “If we formulate an additional response, it will be after we’ve had the opportunity to look at these drafts and evaluate the situation.—

“Though we’ve not yet responded to Congressman Boehner’s letter, we greatly appreciate his seeking input from us,— she added.

Boehner’s office was undeterred despite the lack of response so far and said it would continue to push for the removal of the provision because of the critical importance to the nonprofit sector.

“In these troubled economic times, the last thing the government should do is penalize charities — in addition to churches, synagogues and mosques — that are doing vital relief work in communities across America,— Boehner spokesman Michael Steel said.

Boehner is not the only Republican Member to express concern about the provision; Rep. Roy Blunt (Mo.) joined Sens. Bob Bennett (Utah), Kit Bond (Mo.) and Sam Brownback (Kan.) in condemning it during a press conference Thursday.

GOP operatives say they aren’t surprised Republicans have targeted the nonprofit provision, in part because they say the Obama administration has not staked out a clear view on the issue.

“It makes sense for the GOP to put a spotlight on issues like charitable deduction. Damaging the charitable deduction will have an impact on nonprofits, and it’s an area where [the Obama administration] hasn’t expressed their voice clearly and concisely,— said Ron Bonjean of the Bonjean Co. Bonjean was a former top GOP Hill staffer.

Other Republicans have been moving to curtail the nonprofit community’s ability to lobby Congress.

Budget watchdog group OMB Watch sent an e-mail blast Monday to 40,000 people, drawing attention to an amendment that Rep. Virginia Foxx (R-N.C.) added to the Generations Invigorating Volunteerism and Education Act, which prohibit organizations that receive the national service funds from using those funds from lobbying.

Calling the amendment a “poison pill,— OMB Watch wrote that the provision “would have far-reaching, negative consequences for nonprofit advocacy.—

A similar provision could be added this week to the Senate’s Serve America Act.

“The practical issue for us is a fundamental free-speech issue,— said Lee Mason of OMB Watch. “You are going to tell an organization that you can’t even … co-locate with an organization that does lobbying of any sort if you receive these community service grants.—

Republicans are hardly the only group taking issue with the provision.

Independent Sector, the national leadership forum for nonprofit foundations and corporations, has been meeting with House and Senate leadership about the charitable deduction issue, according to the group’s president, Diana Aviv.

“We are at this point trying to find a way to pay for health care other than through putting a cap on charitable deduction,— Aviv said.