In a mere 14 hours Tuesday, voters will make quick work of a sleepy primary and set New Jersey up for one of the nation's most exciting congressional races.

Republicans will try to push back the weakening Democratic wave that swept President Obama into office two years ago. Freshman Rep. John Adler, the first Democrat since the 1860s to win the district that spans Ocean and Burlington Counties, plus Cherry Hill in Camden County, will try to hold on in that changing tide.

Outside the district, Republicans in Gloucester and Camden Counties will choose their freeholder nominees in contested primaries. Evesham Township will have its first-ever primary because voters there changed elections from nonpartisan to partisan. Races for the U.S. House top the ticket this year in New Jersey, and Adler is the only sitting South Jersey incumbent with a tough battle ahead.

A lot - or maybe not enough - has happened in the country and his Third District since 2008, when Adler captured the seat.

Voters have become impatient as they wait for economic turnaround. Tea party groups have sprung up to protest bank bailouts and health-care programs.

But Sharon Schulman, director of the Hughes Center at Richard Stockton College, said she didn't know whether this race would experience much of a tea party effect, even though the groups have screened and endorsed candidates. "I don't know if the tea party can turn people out," she said.

Analysts believe that Republicans are likely to gain House seats in the 2010 races, and that the Third District seat is among about 80 in play.

"This will be a very competitive race," said David Wasserman, the House campaign expert with the nonpartisan Cook Political Report. "But Adler is one of the most talented campaigners in the freshman class. He knows the right time to strike, and he knows how politics works. He's been at this for three decades. That is such a huge advantage even in a tough climate like this one."

But first the primaries.

On Tuesday, Adler faces an underfunded, barely known Democrat in Barry Bendar, 54, of Forked River, who says he is running because he's angry with Adler for voting against Obama's health-care plan. But because Bendar, the Lacey Township Democratic chairman, has been unable to get his message out, his candidacy will not become a test of Democratic disappointment in Adler's vote.

Turnout for Adler in the primary may indicate whether Democrats are angry over the health-care vote, Wasserman said.

"Adler will be able to easily win this primary, but he could end up with a lesser share of the vote than one might expect against a token opponent," Wasserman said. The more liberal Democrats who tend to vote in a primary "are upset with Adler's vote on health care" and could stay home Tuesday, he said.

Before entering the House, Adler, 52, of Cherry Hill, was an 18-year state senator and served on the Cherry Hill Township Council.

In the Republican primary, political newcomer Jon Runyan, 36, of Mount Laurel, a former Eagles offensive lineman, has a tougher challenge. He faces Justin Murphy, 44, of Medford, who came in a strong third in the 2008 primary for the House seat.

Murphy, a lawyer, Navy veteran, and former Tabernacle councilman, has built a coalition out of tea party and antiabortion groups and dissident Ocean County Republicans.

Runyan tried to ignore Murphy, but he did note Murphy hadn't voted in the 2008 primary, indicating he was concerned about his upstart opponent. In response, Murphy distributed copies of the sign-in sheets from his polling place to show he had voted.

Runyan's campaign consultant, Chris Russell, said Runyan had taken the shot in reaction to some nasty blog postings allegedly from Murphy supporters and not in any belief that the race is close.

Runyan, however, mailed literature to GOP voters over the weekend calling Murphy a "fake conservative."

And, in the final days of the primary campaign, stories circulated saying Murphy was a rent deadbeat and diverted campaign money for personal use. Murphy vigorously denied both allegations.

He said he had an ongoing dispute with a former landlord over a leaky toilet, mice, mold, and a lack of heat. He moved out last December. As for diverting campaign funding, Murphy said he had taken a onetime $300 paycheck from his campaign account, which Federal Election Commission rules allow.

While Runyan and Murphy seem to agree on most issues, Murphy says he opposes abortion, and Runyan says he does not.

Runyan is well-known on the western side of the district, where more than a few Eagles fans live. And he has the preferential county line on the ballot because he is endorsed by all three county party organizations.

One major factor missing from this race is the bitter feud between the Burlington and Ocean County Republican machines that marked the 2008 primary after Rep. Jim Saxton retired after holding the seat for 24 years.

Both county GOP parties agreed on Runyan early in the race after a potentially strong Ocean County candidate, Toms River Councilman Maurice "Moe" Hill, a dentist and retired admiral, pulled out. Hill said he could not compete with Runyan's promise to spend his own money to win.

Runyan, though, has put in only $100,000 of his money and has been unclear about how much he'll invest in his new career. Among his contributors are Eagles coach Andy Reid and Reid's wife, Tammy, who gave a combined $2,400. And Runyan's coach from the San Diego Chargers, Norv Turner, contributed $1,000.

Money will play a major factor in the general election, So far, Adler has reported raising $2.2 million to Runyan's $225,815.

Both have used the primary to preview their fall strategies.

Runyan plans to run on state issues, calling Adler a Trenton tax hiker and a liberal disguised as a moderate.

Adler threw out a kitchen sink's worth of attacks on Runyan in May, saying Runyan was shallow on the issues, paid his taxes late, and has a farmland tax break on his 25-acre estate in Mount Laurel.

Runyan uses the land to graze four donkeys and harvest timber. He held a news conference during the primary to acknowledge his tardy taxpaying habits, saying he wanted to get out in front of any attacks Adler might have in mind.

The 14-hour hurdle that both must clear before they can have at each other starts when the polls open at 6 a.m. and ends when polls close at 8 p.m.

Contact staff writer Cynthia Burton at 856-779-3858 or cburton@phillynews.com.