By most metrics, these House members probably should have lost already.

And yet, like the white whale in “Moby Dick,” these races have a habit of slipping away from the opposition.

The following handful of House members win re-election by defying the odds. They represent unfavorable districts and withstand millions in negative advertisements — yet they stay at the top of the opposition’s target list cycle after cycle.

Last cycle, Roll Call deemed six seats “white whales,” split between the parties. Three of the chosen lost their re-election bids: former Reps. Mark Critz, D-Pa., Robert Dold, R-Ill., and Ben Chandler, D-Ky.

The 2014 collection of white-whale seats includes more vulnerable Democratic incumbents than Republicans.

Democrats argue that this speaks to the political savvy of some of their most vulnerable members. They exemplify the surviving Blue Dogs, who return to Congress thanks to strong campaigns and personal brands in their respective districts.

For Republicans, the races present opportunities to knock off these surviving Democrats. In many cases, if the GOP wins these seats, it puts the party in a position to hold the district for several cycles to come.

Republican White Whales

Minnesota’s 6th District

The Hunt

Democrats have eyed Rep. Michele Bachmann’s district since it was an open seat in 2006. But courts redrew the district ahead of
last cycle to include a more conservative electorate.

Still, Democrat Jim Graves stunned both parties by coming within 1 point of defeating Bachmann, even after a late entry into the race. His performance only encouraged Democrats looking at 2014.

What’s Different This Cycle?

Bachmann’s retirement changed the nature of this race, making it more difficult for Democrats to pick up the seat.

Graves, who had announced earlier this year that he was back for Round 2, saw this was the case; he dropped out of the contest on Friday.

Without Bachmann, Democrats will have a difficult time fundraising in this district, especially now that they don’t have a candidate in the contest.

Democrats’ best hope is if a “Bachmann 2.0” candidate emerges from the primary, thanks to the Gopher State’s unique party endorsement system. Democrats will have to wait until August 2014 for those results.

So for now, a Democratic pickup in this district looks near impossible.

California’s 31st District

The Hunt

Meet the “baby beluga” of the bunch.

Democrats were on track to pick up this seat last cycle. But California’s new jungle primary system — where the top-two vote-getters advance to the general regardless of party — allowed several Democrats to splinter the party’s vote. As a result, two Republicans — including Rep. Gary G. Miller — advanced to the general election.

Miller won, and the seat got away. This cycle, Democratic Congressional Campaign Committee Chairman Steve Israel named the district as one of his top four targets of 2014.

What’s Different This Cycle?

Not too much. Democrats have three candidates so far in this targeted race, even though party strategists say they learned their lesson  last cycle.

The DCCC is backing Redlands Mayor Pete Aguilar, who lost his bid here in 2012. But two other Democratic candidates — former Rep. Joe Baca and lawyer Eloise Reyes, who may have the backing of EMILY’s List — have announced their candidacies in the race.

Democratic White Whales

Utah’s 4th District

The Hunt

A perennial target, Democratic Rep. Jim Matheson’s brand in this GOP district is the envy of his fellow Blue Dogs.

In 2012, the GOP’s strategy was three-pronged: Redraw Matheson’s district, capitalize on Mitt Romney’s strong turnout in the state and recruit a rock-star candidate, Saratoga Springs Mayor Mia Love.

It didn’t work. Matheson’s margin narrowed, and the DCCC was forced to spend on his behalf, but Republicans still came up 768 votes short. Meanwhile, President Barack Obama got 30 percent of the vote in the 4th District.

What’s Different This Cycle?

Love is back for a rematch, and she is starting her campaign earlier than last cycle. The state GOP’s nomination via convention system forced Love into a late start in 2012. This cycle there is little evidence of a competitive primary.

Republicans criticized Love’s team for its management of her 2012 race. This cycle, she’s hired a top gun early: Sen. Orrin G. Hatch’s top campaign consultant.

Arizona’s 2nd District

The Hunt

Republicans have played hard for — and lost — this competitive Tucson seat in five straight elections. In fact, the 2012 special election here inspired the white whales feature last cycle.

The GOP experienced its most high-profile loss here in June 2012, when Rep. Ron Barber won the special election to succeed his former boss, Democratic Rep. Gabrielle Giffords.

But the GOP’s most discouraging defeat came several months later, in November. Barber defeated one of the GOP’s most highly touted candidates, retired Air Force Col. Martha McSally, by about 2,500 votes.

What’s Different This Cycle?

McSally is considering a rematch in this district. Republicans argue that if she runs, she can win — as long as she takes enough time to build a serious campaign.
The other obvious difference is the top of the ticket. Barber will seek re-election without Obama on the ballot, which could help or hurt him depending on the political environment.

Georgia’s 12th District

The Hunt

Last cycle, Rep. John Barrow stunned Democrats and Republicans by holding on to this conservative district. Until last cycle, Barrow had survived four re-election battles, often with a comfortable margin of victory, despite the GOP’s best efforts  to oust him.

In 2012, Barrow sought re-election in redrawn, more conservative territory. Outside groups dumped $3.2 million to defeat him.

But Barrow held on, beating Republican nominee Lee Anderson by 7 points. Obama received 44 percent on the same ticket.

What’s Different This Cycle?

Privately, Republicans said Anderson was a lackluster candidate to challenge Barrow. They argue that with a better candidate in the race, they can defeat the Democrat.

The National Republican Congressional Committee named this seat to its new Red Zone program. The distinction is granted only to House districts that voted for GOP presidential candidates in the past three cycles but are represented by a House Democrat

North Carolina’s 7th District

The Hunt

Rep. Mike McIntyre, a moderate Democrat, has held on to this district for nine terms. In 2010, McIntyre had a serious GOP challenger but survived with a comfortable margin.
But in 2012, state lawmakers redrew his district to make it more favorable for the GOP, and outside groups funneled nearly $3.7 million into the district to oppose McIntyre.
McIntyre squeaked out a victory, beating Republican challenger David Rouzer by a mere 654 votes.

What’s Different This Cycle?

Republicans say that without a presidential race to help turn out the Democratic base, they can pick up McIntyre’s seat.

Rouzer has already announced he will mount a rematch against his former foe.