As Republican lawmakers lead the charge to cut off public funding to National Public Radio, which has been under fire ever since it sacked Juan Williams last month, the network insists it gets no more than 3 percent of its total budget from taxpayers.

But one analyst has argued that NPR's $166 million budget is actually made up of more than 25 percent of taxpayer dollars and that its member stations across the country haul in another 40 percent of public funds.

Mark Browning of the American Thinker, a conservative online publication, made his calculations based on publicly available information on NPR's website.

But an NPR spokeswoman said Browning's "figures and assumptions are simply inaccurate."

A report by Congress' research arm, released late last month, could only identify about 4 percent in public funding to NPR. That's because NPR's financial structure is so complex and opaque, an aide to Rep. Doug Lamborn, R-Colo., told FoxNews.com.

Lamborn's legislation to end taxpayer funding of PBS and NPR, which didn't get far this year, will likely gain more support next year now that Republicans have captured the House.

Browning starts his analysis with NPR's roughly 900 member stations across the country, which provide 40 percent of the organization's annual revenues. Browning says that money amounts to 20 percent of taxpayer dollars for the Washington-based NPR.

Revenues for the local NPR affiliates stem from a number of sources, including 5.8 percent from federal, state and local governments, 13.6 percent from universities, and 10.1 percent from the Corporation for Public Broadcasting, or CPB.

But Browning noted that the federal government provides 99 percent of CPB's funding and asserted that more than 10 percent of the university funding is fueled by tax dollars based on the assumption that three out of four university-supported stations are publicly funded.

That adds up to 25 percent of taxpayer money for the NPR member stations.

Anna Christopher, a spokeswoman for NPR, told FoxNews.com in an e-mail that to conclude that any more funds in addition to the 10.1 percent from CPB and the 5.8 percent from governments come from taxpayers "is entirely speculative."

But Browning didn't stop there. He contends that because donations from individuals, businesses and foundations are tax-deductible, they are subsidized by the government.

Member stations get 32.1 percent from individual contributions, 21.1 percent from business donations and 9.6 percent from foundations.

Browning estimated that the gifts on average result in deductions at the 25 percent tax bracket and argued that 16 percent of the money from those categories, which add up to 64 percent of station funds, is subsidized by the tax code.

"In the end, then, local NPR affiliates derive something like 41 percent of their funding from taxes, either directly or indirectly," he wrote.

Because half of NPR's budget is comprised of local station money that is 40 percent derived from taxes, then 20 percent of NPR's budget comes indirectly from taxpayers, Browning concluded.

Browning also argued that at least 3 percent of the 10 percent funding that comes from grants and contributions category comes from taxes via deductions or taxpayer gifting.

All told, Browning says "it is not unreasonable to assert that more than 25 percent of NPR funds from outside sources actually comes from taxpayers."

"That's not an overwhelming portion of the budget, but it's a long way from 2 to 3 percent," he wrote.

But Christopher, the NPR spokeswoman, said Browning's analysis isn't reasonable.

"Forty percent of NPR's budget comes from station programming fees," she said. "As station budgets consist of some federal and state support, and stations in turn pay NPR, you could argue that a small – unquantifiable – percentage of that support filters indirectly to NPR."

"Quantifying that amount is imperfect, and impossible math," she said.