When two Members face off in the same district, the result is something like a House race on steroids.

Ask a Capitol Hill veteran, and he or she probably remembers something from the top battles between Members of 2002. Rep. John Dingell (D-Mich.) against then-Rep. Lynn Rivers (D-Mich.) and Rep. Tim Holden (D-Pa.) versus then-Rep. George Gekas (R-Pa.) were just two.

During the last redistricting cycle 10 years ago, 16 Members faced a colleague: Eight each in primaries and general elections. With nine Congressional maps signed into law, the 2012 cycle is on track to showcase even more Members facing each other than a decade ago. That’s in no small part due to an independent redistricting commission in California, which is overhauling a Congressional map that features 53 incumbents.

Obviously, much can still change between now and November 2012. For example, California and Pennsylvania are far from finalizing their maps, and Louisiana’s new House districts must be approved by the Justice Department. But even so, several Members are already gearing up to face off against a colleague next year.

Here is our take on the five most contentious races between Members on tap for 2012.

California

Rep. Howard Berman (D)
15th term (70 percent)
Current district: Part of the San Fernando Valley
Cash on Hand (as of March 31): $1.1 million

vs. Rep. Brad Sherman (D)
8th term (65 percent)
Current district: Part of the San Fernando Valley; part of Burbank
Cash on Hand (as of March 31): $3.1 million

Call it a battle between man — er, men. The expected primary between Democrats Berman and Sherman in Southern California will be one for the ages. The independent California redistricting commission has proposed a single, Democratic-leaning West San Fernando Valley district — the home base area for both Berman and Sherman. And both appear to be gearing up to run there.

The two Democrats have had a tense relationship in the past as a result of the last round of redistricting, although it’s thawed significantly in recent years. A primary between Sherman and Berman would almost certainly revive those tensions and set up the premiere intra-party race of the cycle.

Democrats warn that the commission has only released its first draft  and stress they are expected to heavily revise their plan for the Southern California region before the final map is released at the end of the summer.

In the meantime, Berman and Sherman have said they will run in the same district. Both Democrats released their statements declaring their intentions just a couple of hours after the maps were released.

Sherman starts out with a geographical advantage, given half of the newly drawn district is part of his current territory. However, Berman has stronger connections to the fundraising community in Southern California and the Los Angeles Democratic Party, which could also give him a leg up in the primary.

Either way, Democrats will want to do everything possible to avoid this Southern California cage match.

Iowa

Rep. Tom Latham (R)
9th term (66 percent)
Current district: North and central — Ames, Mason City
Cash on Hand (as of March 31): $984,000

vs. Rep. Leonard Boswell (D)
8th term (51 percent)
Current district: Central and east central — Des Moines
Cash on Hand (as of March 31): $174,000

For years, Republicans have targeted and attempted to take out Boswell, but to no avail. The Des Moines-area Democrat won re-election in the banner GOP year of 2010 in no small part because Boswell did not have top-tier competition.

This cycle, the independent Iowa redistricting commission inadvertently helped the GOP find the perfect candidate to challenge Boswell: Latham. The GOP lawmaker announced he would take on Boswell in the redrawn 3rd district in southwest Iowa after one seat was eliminated following reapportionment.

There are plenty of reasons this will be a top race. The new 3rd district includes more competitive territory than Boswell’s current seat. President Barack Obama carried the current 3rd district with 54 percent, but the redrawn 3rd district would have given Obama 52 percent.

Latham is already running hard, working the new district and regularly appearing at local events. At the end of March, he had an $800,000 cash-on-hand advantage over Boswell, although fundraising is not expected to be a problem for either Member in the race. It’s also worth noting that Latham is especially close to Speaker John Boehner (R-Ohio), so it’s hard to see how he won’t have whatever resources he needs to compete.

Boswell has a geographical advantage because there’s more of his current district in the new 3rd district than there is of Latham’s current district. Considering that Boswell has been representing the area since 1996, Latham will have to work to introduce himself to a swath of new voters in southwest Iowa.

Louisiana

Rep. Charles Boustany (R)
4th term (Unopposed)
Current district: Southwest — Lafayette, Lake Charles
Cash on Hand (as of March 31): $694,000

vs. Rep. Jeff Landry (R)
1st term (64 percent)
Current district: South central —New Iberia, Houma, Chalmette
Cash on Hand (as of March 31): $172,000

The race between four-term Boustany and freshman Landry will provide a marquee Republican-establishment-vs.-tea-party primary battle. Louisiana lost one House seat following reapportionment, shrinking the delegation to six. Republicans were forced to keep at least one majority-black district in order to adhere to the Voting Rights Act, which meant one GOP Member would lose his seat under the new map. As the most junior Member in the delegation, Republicans picked Landry as the odd man out when they redrew the map earlier this year.

Landry has indicated he wants to run for another term, and sources say he is looking at all his options. However, Landry’s most likely path to re-election is against Boustany, given much of his current district was folded into Boustany’s redrawn district in southern Louisiana.

Landry had ample tea party backing in 2010, which he could look to again for a boost against Boustany. The latest hint he is differentiating himself from the GOP establishment to prepare for a primary bid? When the entire House Republican Conference was invited to a meeting with the president earlier this month, Landry respectfully declined to attend. Boustany, who has close ties to GOP leadership, attended the meeting.

A primary bid against Boustany could settle a political score for Landry. After all, Boustany led the delegation’s work with the state Legislature to draw the new maps and therefore played a role in trying to orchestrate Landry’s ouster.

There is one cautionary note about this primary battle. The Justice Department still has to clear the Congressional map, which means the lines could still change before they’re put into practice next year, but that’s unlikely.

Illinois

Rep. Adam Kinzinger (R)
1st term (57 percent)
Current district: South Chicago exurbs — Joliet; part of Bloomington-Normal
Cash on Hand (as of March 31): $237,000

vs. TBD

Illinois Democrats drew a new Congressional map that left their GOP colleagues in disarray, pushing many GOP Members into a district with a colleague or into heavily Democratic districts. Freshman Kinzinger bore the brunt of the redraw, which pushed his home into the same overwhelmingly Democratic district as Rep. Jesse Jackson Jr. (D).

The new map that was signed last week by Illinois Gov. Pat Quinn (D) does not leave Kinzinger with any good options — and all of them almost certainly involve running against another Member on mostly foreign turf.

Kinzinger would lose if he ran for re-election in Jackson’s predominantly black and urban district. He could move to run in the redrawn Democratic-leaning 11th district southwest of Chicago, but Republicans say seven-term Rep. Judy Biggert (R) is already eyeing that seat.

Unfortunately for Kinzinger, his best option in the general election would also mean his worst primary challenge. He could run in the redrawn Republican-leaning 16th district, where much of his current territory lies. But 10-term Rep. Don Manzullo (R) is already planning his re-election campaign in the 16th district, which means Kinzinger would be in a tough primary race against one of the delegation’s most powerful Republicans.

Illinois Republicans, including Kinzinger, announced last week they will not comment on the map while it’s headed to court. However, Kinzinger might have accidentally hinted where he wants to run. A couple of days after the map was initially released in late May, a GOP county chairman said Kinzinger told him he wanted to challenge Manzullo in the 16th district. Kinzinger’s office immediately pushed back on a potential challenge, and the Congressman has been mum ever since about where he would run.

Pennsylvania

Rep. Mark Critz (D)
1st full term (51 percent)
Current district: Southwest — Johnstown
Cash on Hand (as of March 31): $152,000

vs. Rep. Jason Altmire (D)
3rd term (51 percent)
Current district: West — Pittsburgh suburbs
Cash on Hand (as of March 31): $133,000

Pennsylvania Republicans are months away from releasing a map, but there is little doubt that southwestern Democrats Altmire and Critz will be drawn into the same district. Republicans have eyed the 4th and 12th districts for some time, and one simple redraw could easily solve two perennial problems for Keystone State Republicans.

First off, Republicans divide and conquer some of the GOP territory in Critz’s amoeba-shaped 12th district. His predecessor and former boss, the late Rep. John Murtha (D-Pa.), worked for years to save the district in previous redistricting battles, but Republicans would prefer to cut up the territory and move heavily Democratic Johnstown to another area.

Meanwhile, Altmire has become a perennial GOP target on the northwest side of Pittsburgh. Pennsylvania Republicans have failed to knock off Altmire since he defeated then-Rep. Melissa Hart (R) in 2006.

Typically, the more junior Member has a disadvantage in these races, and Critz came to Congress only a little more than a year ago. But Critz has already made it clear he will not go down without a fight, campaigning heavily in the district and working local party meetings.

Critz is also more likely to have a key coalition on his side: organized labor. Local unions are not pleased with Altmire for his more moderate voting record, including voting against the Democratic-led health care overhaul last year. Critz was not in Congress yet when Members voted on the controversial bill.

The question of who has the upper hand in this race will depend on the geography of the new district. Given population movement in the region, that should be Altmire.