Burlington County Republican leaders recruited Runyan to run against freshman U.S. Rep. John Adler (D., N.J.) in what is expected to be one of the most competitive midterm races in the nation. The Third District includes Cherry Hill in Camden County and runs through Burlington and Ocean Counties.
Chris Russell, Runyan's campaign manager, said the candidate was "in compliance with the law and does what any other taxpayer in his situation could do."
"With anyone who pays $60,000 in taxes, it's hard to say he's getting a break," he said.
Runyan bought his home and land in 2000 for $980,000, according to deeds. At the time, it qualified for the farmland assessment. Russell argued Runyan was just following the practice of the previous landowner.
"He considers himself a steward of his land, and that's what farmland assessment is supposed to do," said Russell.
Runyan didn't always have the four donkeys. Last January, the township assessor wrote to Runyan that one donkey wasn't enough to justify the tax break.
"Although your application was approved for 2009, this acreage will not qualify in the future if you do not have enough animals to justify the five acres," the letter said.
A year later, Runyan reported having four donkeys grazing on five acres, and kept his tax break.
Russell said Runyan had long planned to breed the donkeys but wasn't ready to do that just yet.
About 900 of Mount Laurel's 14,000 acres get a tax break with the farmland assessment, according to a Department of Treasury report. The average tax for a Mount Laurel home's land and improvements is $4,300, according to the state Department of Community Affairs.
Farmland assessments have been credited with helping to save thousands of acres of farmland in the most densely populated state. To qualify, a landowner must devote at least five acres to agricultural purposes. But the program also has been fraught with controversy.
A 2008 audit by the Office of Legislative Services found that towns, counties, and state departments charged with verifying whether a property merits the tax break did not routinely do so.
When the tax assessor told Runyan that one donkey wasn't enough, she cited that audit, which noted that one landowner was getting the tax break for using his land to graze a single sheep.
Based on recent campaigns, candidates taking advantage of the farmland tax break can expect their opponents to use it against them.
New Jersey's property taxes are among the highest in the nation, much to the frustration of voters. In polls during last year's governor's race, voters listed the economy and property taxes as their highest concerns.
Former State Sen. Ellen Karcher, a Monmouth County Democrat, watched her 2007 reelection race fall apart when her Republican opponent ran a television ad showing Karcher's home and noting that she took the tax break on the seven acres surrounding it.
Republican U.S. Rep. Scott Garrett found himself defending his tax break on 10 acres in his 2008 reelection race. He survived in his overwhelmingly Republican district, which covers parts of Warren and Sussex Counties.
And former Gov. Christie Whitman came under attack because she had a farmland assessment on 50 acres of her property in Far Hills.
Russell said he expected attacks from Democrats.
"I think Jon realized when he got into this race that when you enter politics - for better or worse - your life is an open book. He's comfortable with who he is and what he's done with his life. With the farmland assessment, he's done nothing but what's on the books."
Before Runyan can face Adler, he'll have to get support from Ocean County Republicans or face a primary.
While he has GOP support on his home turf, Republicans in Ocean County are still fielding candidates for a race that many in the party believe is winnable. Because Adler doesn't have President Obama at the top of the ticket, as he did in 2008, Republicans think voter frustration with the economy will help them recapture the seat.
Runyan, 36, played eight years on the Eagles' offensive line before an injury sidelined him. He signed with the San Diego Chargers as a backup in November, saying that would be the end of his football career.
Contact staff writer Cynthia Burton at 856-779-3858 or email@example.com.