Every 10 years the pool of Members eligible for this list becomes larger thanks to redistricting.

This cycle, more Members than normal are in jeopardy because of a nonpartisan redistricting effort in California that has created more competition than the state has seen in two decades.

Even so, there is only one Californian on the list. But half of the Members here hail from the two states that passed the most politically gerrymandered maps: Illinois and North Carolina.

We chose not to include any Members who are squaring off against a fellow Member because most of those races — at least at this point — look like fair fights. That may change by the next time we do this list, when more states will have completed redistricting.

We also fully expect several of these Members will not make our next list because they will have announced their retirement.

Honorable mentions go to Reps. Charles Bass (R-N.H.), John Conyers (D-Mich.), Lloyd Doggett (D-Texas), Donna Edwards  (D-Md.) and Dan Lungren (R-Calif.). 

Roll Call’s Top 10 Vulnerable Members, in alphabetical order:

John Barrow (D-Ga.)

4th term (57 percent) | Cash on Hand (Sept. 30): $692,000

Barrow has been targeted for defeat before, but the GOP finally seems to have the Congressman’s number in 2012 — via redistricting. Several Republicans have lined up to run, and all indications are Barrow won’t go down without a fight. But key for him is the fact that Democratic-leaning portions of Savannah were removed and replaced with very Republican Augusta suburbs. The result: What was a 54 percent Barack Obama district is now a 59 percent John McCain district. Enough said.

Roscoe Bartlett (R-Md.)

10th term (61 percent) | Cash on Hand (Sept. 30): $261,000

Bartlett was protected in the 2001 redraw because Democrats targeted then-Rep. Connie Morella (R), who lost because her district became so Democratic she couldn’t win. A decade later, Bartlett finds himself in the same position. According to Republicans, his western Maryland district is the most gerrymandered so far this cycle. It swings from an R+13 partisan voting index to a D+4 under the new lines. Bartlett, who will be 86 by Election Day, is vowing to run again and has begun fundraising in earnest. But he remains a retirement possibility once the political reality of the situation sinks in. 

Dan Burton (R-Ind.)

15th term (62 percent) | Cash on Hand (Sept. 30): $323,000

Burton got just 30 percent of the vote in the 2010 primary, so a majority of Republicans in the district voted against him. He once again faces a multicandidate primary, but there are two key differences. First, he faces stronger, and likely fewer, opponents — including a former Congressman. Second, the counties where Burton performed best in the 2010 primary were removed from the district under the new map. Those two factors combined make the climb for someone first elected in 1982 that much more difficult.

Russ Carnahan (D-Mo.)

4th term (49 percent) | Cash on Hand (Sept. 30): $394,000

It’s been months since the new Missouri map became law, but Carnahan still hasn’t said what his political plans are for next year. His options don’t look appealing. Observers doubt he’ll challenge Rep. William Lacy Clay in a Democratic primary where the majority of the electorate would be black. His other option (if he wants to stay in Congress) is to run in the redrawn 2nd district, which favors Republicans. Carnahan could also decide to run statewide. Whatever he decides, the odds currently don’t favor him returning for the 113th Congress.

Robert Dold (R-Ill.)

1st term (51 percent) | Cash on Hand (Sept. 30): $995,000

Dold is a fundraising star among the large GOP freshman class. He’ll need all the bankroll possible to win a second term next year. While by all accounts Dold is a strong Member, he’s in a district that is supposed to elect a Democrat. Redistricting made the district even more Democratic and next year Dold has to run with President Barack Obama at the top of the ticket. One of the few things working in Dold’s favor is that Democrats haven’t produced a very strong field of candidates. But it may not matter.

David Dreier (R-Calif.)

16th term (54 percent) | Cash on Hand (Sept. 30): $774,000

The fact that Dreier has been able to win re-election for the past decade is a testament to his popularity in an increasingly Democratic district and to the incumbent protection redistricting plan implemented 10 years ago. But this cycle, it appears the Rules chairman’s number is finally up. An independent commission — not state lawmakers — redrew California’s lines this time, and the result is a map that leaves Dreier with no good options. He has said he’s hopeful that a lawsuit will prevail in overturning the map, but that isn’t likely. Few strategists in either party expect him to run again.

Larry Kissell (D-N.C.)

2nd term (53 percent) | Cash on Hand (Sept. 30): $251,000

Kissell has had luck on his side or a Democratic wind at his back in his previous two victories. But he appears to need a miracle to hold on in 2012. Republicans unraveled a Democratic gerrymandered map and replaced it with one that endangers most of the state’s white Democrats. Kissell rode the Democratic wave to victory in 2008 helped by black turnout in Charlotte and Barack Obama at the top of the ticket. But Obama’s presence is not expected to give him that same boost next year given that the black population in Kissell’s redrawn district dropped by 10 percent.

Mike McIntyre (D-N.C.)

8th term (54 percent) | Cash on Hand (Sept. 30): $555,000

McIntyre got a serious scare in 2010, when he held on to win despite the national GOP wave. Republicans in the state redrew the map to make sure the Blue Dog Democrat won’t be able to hold on again if another wave hits. In fact, it won’t even take a wave. McIntyre is likely to face a much stronger challenger next year. He will need to put all of his retail campaigning prowess to use to win a 9th term.

Bobby Schilling (R-Ill.)

1st term (53 percent) | Cash on Hand (Sept. 30): $450,000

Schilling literally embodies the story of the 2010 GOP wave. A pizza restaurant owner, he was one of the many political outsiders who rode swing voters’ discontent to victory in the president’s home state. In 2012, Schilling will have the chance to prove his election wasn’t a fluke — but Democrats haven’t made it a fair fight. A Democratic-led redraw made what was a Democratic-leaning swing seat more safe Democratic territory. Schilling has proved he can surprise prognosticators, and this will definitely be an interesting contest to watch. 

Heath Shuler (D-N.C.)

3rd term (54 percent) | Cash on Hand (Sept. 30): $233,000

There are still murmurs that Shuler might decide to retire instead of seek re-election in what is now the most Republican district held by a Democrat in the state. Shuler is no stranger to winning in tough territory. But next year he’ll have to win in a district that no longer contains the Democratic bastion of Asheville. It’s a tall order, even for a former standout college quarterback and glad-handing politician at the top of his game. If Shuler runs, this is guaranteed to be a top race to watch.