Many donors view the race as a microcosm of their party's struggle to control Congress. Republicans need a net gain of 39 seats to dominate the House, and the Third District race is too close to call, say several independent pollsters.
When Adler voted against President Obama's health-care overhaul, he "lost any kind of luster amongst Democrats in his district. I don't know if he lost votes, but he lost enthusiasm," Weingart said.
And Runyan, he said, "hasn't proved to be a particularly charismatic or, so far, memorable candidate."
Despite the high stakes, analysts predict that fewer than half the district's 460,000 registered voters will have their ballots counted Tuesday. Volunteers for the candidates plan to make thousands of phone and house calls to raise that number.
"We want to chase down every vote," said Kristin Antonello, Runyan's campaign manager.
Though early polls had Adler, 51, of Cherry Hill, ahead of Runyan, 36, of Mount Laurel, the campaigns have known for months that they would now be within a hair of each other. So on Election Day it's up to the political machines.
They started to tune up their get-out-the-vote operations in the summer, figuring out who would support their candidates and contacting them.
Some votes were locked up early. By Friday, mail ballots had been received from about 11,800 people - 5,800 Republicans, 4,000 Democrats, and 2,000 unaffiliated voters. More, including some that are hand-delivered, are expected by Tuesday, when they will be tallied.
This weekend, Adler and Runyan are swinging through the 925-square-mile district, which runs from the Delaware Bay in Burlington County and through the Pinelands to the sand in Ocean County. Also in the district is Cherry Hill in Camden County.
Each is spending time in the battleground areas of Toms River and Berkeley Township in Ocean County and Burlington County's Evesham, Moorestown, Medford, and Mount Laurel.
Adler has visited reliably Republican Ocean County every other weekend since his House campaign two years ago. He has held more than 120 town meetings in the district to introduce himself.
Runyan has drawn recent visits by Gov. Christie and Republican National Committee chairman Michael Steele. He may get a lift Sunday night from Republican lightning rod Sarah Palin, the former Alaska governor, at a Toms River tea party rally. Palin's participation won't be confirmed until shortly before the event, said the rally's chief organizer, Connie Sherwood.
Among New Jersey's 13 House districts, the Third has the most voters older than 65 and the highest percentage of homeowners, according to Rutgers' Legislative District Data Book.
To reach the older audience, Democrats have pointed out that Runyan is supported by groups that want Medicare and Social Security privatized. Runyan has said vehemently that he is against such a change.
To capture homeowners, who pay New Jersey's notoriously high property taxes, the candidates also have had at each other.
As a state senator for 17 years, Adler voted to raise taxes and spending, Runyan has said. On the contrary, Adler has countered: In Trenton, he tried to cut taxes.
Since the race's earliest days, Adler and friends have slammed Runyan for taking advantage of a legal property-tax break on his 25-acre Mount Laurel estate. Runyan pays less than $500 in tax on the 20 acres where he grazes four donkeys and harvests timber. He has pointed out that he pays more than $61,000 on the five acres where his mansion sits.
Runyan has campaigned on a promise to cut taxes but has offered few specifics about the programs he would trim or eliminate. He has boasted about his lack of political experience, saying Washington veterans have failed to solve the nation's problems.
Adler, too, has promised to cut taxes. He has said he voted against more than half the spending bills put before him since his Jan. 6, 2009, swearing-in.
Promises to cut taxes and spending work well in the generally right-of-center district, where registered Republicans outnumber Democrats, 141,391 to 130,082. The largest number of registered voters are independents, who swung for Obama in 2008 and Christie in 2009.
But voters who are worried or angry about the economy have learned little about the issue from the candidates' televised political ads.
Many of the commercials were broad political or narrow personal attacks. Adler talked about Runyan's farm and called him a scammer. Runyan cast Adler as a left-wing drone in House Speaker Nancy Pelosi's hive.
Both campaigns are using outside support. Registered Republicans can expect robotic calls from Christie in the hours before the election. Adler has gotten assists from public employee unions, including the New Jersey Education Association and the Communication Workers of America.
The campaigns also are going after "soft" voters from the other side - Republicans or Democrats who skip primaries but regularly vote in general elections.
Adler has subtly tried to cast Runyan as a dumb jock. At an Ocean County College forum, Adler - a Harvard University-educated lawyer - asked Runyan if he disagreed with any U.S. Supreme Court decisions rendered in the last 15 years.
Runyan named the Dred Scott decision - an 1857 ruling that upheld the practice of slavery. A YouTube video of the exchange, complete with a snickering audience, has received thousands of hits.
At a forum at Ponzio's Diner in Cherry Hill last week, Adler asked Runyan if he had read the House bills he was criticizing. Runyan said he had read a couple, but was not specific.
Runyan has called Adler a fraud and accused him of propping up a fake candidate to siphon votes from the Republican. As recently as Friday, he cited a pamphlet that praised Peter DeStefano and criticized Runyan as evidence that Adler had planted the independent, who is running under the tag "NJ Tea Party."
DeStefano has denied getting help from Democrats and is unknown to local tea party groups, which have endorsed Runyan.
No matter who wins, the undisputed victors in the Third District race have been political comics.
A former pro-football player, an Ivy League lawyer, four donkeys, one allegedly fake candidate, and a 19th-century Supreme Court decision: How often does a humorist get material like that?
Contact staff writer Cynthia Burton at 856-779-3858 or firstname.lastname@example.org.