The miniature donkeys that graze at the Mount Laurel homestead of U.S. Rep. Jon Runyan became political fodder as soon as the former Eagles tackle announced his candidacy in 2009. Under a New Jersey law designed to protect farmers from soaring property taxes, Runyan receives a 98 percent tax break on most of his land because he keeps donkeys and sells firewood.

Democrats attacked Runyan, whose median net worth is estimated at $7 million, for taking advantage of a farm program to avoid paying the full tax rate on 20 of his 23 acres.

Two years later, tax breaks for the wealthy are drawing even sharper criticism as Congress fights over how to spur the sluggish economy and manage the country's debt.

Last month, conservative Sen. Tom Coburn (R., Okla.) slammed "millionaires" for taking tax breaks, including agricultural benefits, in a report called "Subsidies of the Rich and Famous."

Coburn focused on federal subsidies, but he also cited New Jersey's farmland assessment, noting that rock stars Jon Bon Jovi and Bruce Springsteen enjoy the same subsidy Runyan receives.

Farm programs, Coburn wrote, were established to "encourage individuals in agricultural pursuits."

"Farmers that are millionaires no longer need this encouragement," he wrote. "Further, a millionaire landowner should not be paid by the government to preserve their land."

Runyan, 38, says he pays his fair share of property taxes and follows the law to keep his farmland assessment.

"It's open space that everybody cherishes, especially here in New Jersey," he said. His critics "don't dig into the overall tax burden . . . . For me, it's almost $62,000."

This year, Runyan paid $61,627.28 in property taxes on the three acres that include his house. For the remaining 20 acres, he paid $123.80.

Republican Runyan defended Bon Jovi and Springsteen - who have actively campaigned for Democrats - for likewise taking the tax break. Bon Jovi raises honeybees, and Springsteen reportedly leases land to an organic farmer. Neither responded to requests for comment made through spokeswomen.

"They're probably in the same boat," he said. "My guess is they're probably paying more because they have bigger homes than I have and the area they live in is an area that's more expensive than it is down here."

Runyan bought his property in 2000 for $980,000, according to deeds.

Josh Schwerin, a spokesman for the Democratic Congressional Campaign Committee, said that just because the tax break is legal doesn't make it right.

"Congressman Jon Runyan has spent his career in Washington protecting tax breaks for millionaires," he said. "As a millionaire himself, it's no shock that Congressman Runyan continues to take advantage of New Jersey taxpayers by outrageously calling himself a farmer."

Runyan is one of 250 members of Congress considered a millionaire, according to a November report from the Center for Responsive Politics. His median net worth is $7 million, according to the center's report, and he made between $1.5 million and $2.5 million in 2009, according to federal financial disclosures based on 2009 tax returns.

To qualify for a New Jersey farmland assessment, a resident must own a minimum of five acres of arable land and generate at least $500 in income from agricultural products or livestock.

That is too lenient, says Republican State Sen. Jennifer Beck of Monmouth, cosponsor of a bill with Senate President Stephen Sweeney (D., Gloucester) to revise the Farmland Assessment Act, a 1964 constitutional amendment.

"People recoil when you have people that have one beehive taking advantage of a program, and they're not truly farmers," she said. "There's a 'fake farmer' charade, and I think when you look at it, there is a moral aspect here as well as a public-policy problem."

Beck wants anyone who receives the farming tax break to produce at least $1,000 worth of agricultural goods annually, a figure the Legislature would revisit every three years. Her bill also asks the state board of agriculture to develop detailed guidelines on what qualifies as a farm.

The $1,000 threshold is a reasonable revision, said Brian Schilling, an assistant professor at Rutgers University and an expert on the Farmland Assessment Act.

Because many farmers work on smaller parcels, sometimes only part time, he argues that the requirements should not become too strict.

"We have over 10,000 farms in this state, and the vast majority of them . . . are very, very small," he said. "There are people who farm for reasons other than 100 percent of their living."

Schilling also said that anyone who meets the standards, regardless of their income, should be entitled to a farmland assessment.

"The farmland assessment is blind to the person; it's about the land," he said.

And even if, like Runyan, a resident generates only a small agricultural income in exchange for a big tax break, the farmland assessment can still benefit the community, Schilling said. The nearly one million acres of assessed farmland in the state consume only a third of services when compared with developed land.

"Cows don't go to school," he said.

But Beck thinks farmland and open space should be taxed differently, as they are in Pennsylvania and New York. She and Sweeney introduced a separate bill that would offer a 50 percent property-tax cut to landowners with at least five acres of subdividable land who give up their development rights in perpetuity.

"Farmland assessment has been used in the state of New Jersey as our open-space program," Beck said. "It was intended for people who work the land or raise livestock."

Runyan almost lost the farmland tax break in January 2009 after Mount Laurel informed him that keeping a single donkey on his property was not sufficient to qualify his acreage as farmland.

A year later, Runyan reported keeping four donkeys and retained the tax break.

Runyan said his plan has always been to breed donkeys, an interest he developed through another breeder. Although Runyan does not use the donkeys for any agricultural purpose himself, they make good companion animals for horses and can fetch between $400 and $1,500 apiece, he said.

Runyan bought two pregnant mares named Echo and Meadow, which gave birth to two more females, Daisy and Lily. Since July 2011, Echo and Meadow, each bred with a male from another donkey owner, have given birth to a fifth female, Angel, and a male, Eeyore.

So far, Runyan has not sold any donkeys. He planned to sell livestock in September 2010, according to a form filed with tax assessor's office in August 2010. But he was not ready then, he said.

Instead, Runyan has met the $500 minimum requirement to keep his tax break by selling firewood. In 2010, he sold eight cords for $920, according to township records. In 2011, he sold six cords for $690.

Runyan said he has always obeyed the law, and if it changes, he will adapt.

"I do almost $1,000 a year as it stands," he said of his firewood sales.

Of the farmland assessment, he said: "There's not a lot of stringent parameters . . . . The law in itself is very vague."