Less than two weeks before Election Day, the parties don’t agree on much — except these House races will be decided by the slimmest of margins.

Candidates in these contests are expected to have a long wait on the evening of Nov. 4. In fact, some of these races will be so close that the winner might not be known for days — even weeks — after Election Day.

Last cycle, nine House races were too close to call on election night. One candidate even attended freshman orientation the following week, before officially losing the race and heading home.

In alphabetical order, here are the House contests this cycle that operatives expect will come down to the wire on Election Day:

Arizona’s 1st District

First elected in 2008, Democratic Rep. Ann Kirkpatrick was ousted from Congress in the GOP wave two years later.

But the decennial redistricting process redrew the district to be friendlier — though still difficult — for Democrats, and Kirkpatrick won a comeback bid last cycle by more than 3 points. Still, Mitt Romney performed better than Kirkpatrick, reaching 50 percent in the expansive district.

This cycle, Republicans targeted Kirkpatrick from Day One. GOP outside groups have spent millions to try and boost her opponent, state Speaker Andy Tobin, to victory. The party is confident they can oust her.

But Kirkpatrick’s ties to the Navajo Nation — a large portion of the electorate here — could save her. With tribal elections overlapping with the midterms, Kirkpatrick might pull off a slim victory.

And no matter who wins, the Grand Canyon State’s notoriously slow ballot counting will make it a long night anyway.

Rothenberg Political Report/Roll Call rating: Tossup

Arizona’s 2nd District

When retired Air Force Col. Martha McSally ran in 2012, the race between her and Democratic Rep. Ron Barber was so close, McSally boarded a plane and attended freshman orientation.

A week and a half later, after provisional ballots were counted, she lost to Barber by about 2,400 votes.

Democrats and, privately, Republicans say Barber has a slight edge two weeks from Election Day. But Republicans have a minuscule — 1 percent — voter-registration advantage in this Tucson-based district. Mitt Romney carried it by a 2-point margin in 2012, when Barber defeated McSally by less than a point.

Operatives expect a similarly small margin for this year’s victor, whoever that is.

Rating: Tossup

California’s 7th District

This district is nearly evenly divided between Democrats and Republicans in party registration. And that’s just one reason this Sacramento-based seat will go down to the wire, according to operatives on both sides.

In 2012, Rep. Ami Bera, D-Calif., unseated now-ex Rep. Dan Lungren by fewer than 10,000 votes to win the district. Bera even traveled to Capitol Hill for freshman orientation without knowing if he had officially won.

Operatives say this cycle’s contest between Bera and former Rep. Doug Ose, a Republican, will be just as close. They add the race will be decided by field operations in what’s expected to be one of the lowest turnout elections in California’s history.

The Golden State’s vote-counting process — in which ballots are dumped in groups at timed intervals — will also make for a long, slow election night. It’s easy to see how ballot counting could continue for days — again.

Rating: Tossup

Illinois’ 10th District

This district located north of Chicagoland votes for Democrats by double digits in presidential races. But down the ballot, voters have shown a propensity to elect moderate Republicans to Congress. Now-Sen. Mark S. Kirk, R-Ill., represented the district for five terms until he ran statewide in 2010.

This cycle, freshman Rep. Brad Schneider, D-Ill., faces former Rep. Bob Dold, the Republican he ousted by a 1-point margin in 2012. Both have raised significant sums of money and are aided by outside groups.

With a competitive gubernatorial contest topping the ticket, operatives say this race will again be a squeaker.

Rating: Tossup

Iowa’s 3rd District

Privately, Iowa Republicans grumble about David Young, the GOP nominee in this open-seat contest to replace retiring GOP Rep. Tom Latham. They argue that this is a good year for Republicans, and Young should have an advantage.

After all, Democrats face headwinds Nov. 4 from the Hawkeye State’s Senate race, where GOP state Sen. Joni Ernst has opened up a lead in polls over the Democrat, Rep. Bruce Braley.

Ernst’s performance is buoying Young in his race against former state Sen. Staci Appel, keeping him in contention in this district, which has no registration advantage for either party. President Barack Obama won the district by 4 points in 2012.

Operatives say the top of the ticket could help Young eke out a win, but it’s far from a done deal.

Rating: Tossup

New Hampshire’s 1st District

For the third time, Rep. Carol Shea-Porter and former Rep. Frank Guinta, R-N.H., will face each other. Guinta defeated her in 2010. Shea-Porter, a Democrat, ousted him two years later. And on Nov. 4, they meet again. They can thank New Hampshire’s volatile political climate for the see-saw cycles. But that makes the Democrat especially vulnerable this cycle, when Obama is deeply unpopular.

The 1st District, located in the eastern half of the state, is also the more friendly for Republicans, compared to the Granite State’s other district. Last cycle, Obama carried the 1st District by a 1-point margin, while Shea-Porter defeated Guinta with less than 50 percent of the vote. In fact, some operatives say Shea-Porter won thanks to presidential year turnout, and a libertarian candidate that siphoned off more than 4 percent of the vote.

This cycle, Democrats in New England said Shea-Porter will get a boost from a gubernatorial and Senate race topping the ticket. But given the district’s partisan breakdown, operatives say this one will come down to the wire.

Rating: Tossup

New York’s 1st District

Democratic Rep. Timothy H. Bishop’s Long Island-based district is a tough seat for Democrats in a good year for the party. Obama carried it by a 1-point margin last cycle.

This cycle, the six-term Democrat has been plagued by an ethical dust-up in which he’s been accused of helping a constituent obtain firework permits for his son’s bar mitzvah in exchange for a campaign donation. The justice department closed its investigation into the incident in September without filing any charges.

But Bishop has squeaked back into office by the skin of his teeth before, too, including in 2010 when he won re-election by less than 1 point.

This time around, Republicans say their recruit, state Sen. Lee Zeldin, is the best they’ve had in a few cycles. And outside groups from both sides of the aisle are up on air here.

Yet both sides, while confident in their chances, say the margin will be slim.

Rating: Tossup

Related Stories:

6 Gubernatorial Races With Potential Congressional Consequences

The 10 Most Vulnerable House Members

Martha McSally Tries to Fly to Victory

Shooting in the Rear View, Ron Barber Drives His Own Way

Roll Call Election Map: Race Ratings for Every Seat

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