As many as one-quarter of the members of the Congressional Black Caucus could face significant primary opposition in their new House districts in 2012, a development that could significantly change the face of the CBC and/or reduce its membership heading into 2013.

With nationwide redistricting slightly more than halfway done, at least 10 of the 41 members of the CBC already have well-known politicians eyeing their new districts.

As Roll Call’s Shira Toeplitz noted on Monday, a few of those members are actually facing matchups with current or former Members of Congress who are white. These members include Reps. Lacy Clay (D-Mo.), Hansen Clarke (D-Mich.), Laura Richardson (D-Calif.) and Jesse Jackson Jr. (D-Ill.).

But others are facing primaries with ambitious black politicians who see opportunities in newly drawn districts.

Rep. John Conyers (D-Mich.), for instance, could face a serious primary challenge from state Sen. Bert Johnson in a Detroit district that takes in lots of new voters. The same goes for Reps. Cedric Richmond (D-La.), Ed Towns (D-N.Y.), Marcia Fudge (D-Ohio), John Lewis (D-Ga.) and Bennie Thompson (D-Miss.).

Richmond and Fudge, in particular, have seen their districts stretched significantly in order to keep their black majorities intact — a requirement of the Voting Rights Act that says black majority districts must be made if they can be made.

Richmond’s new district will extend from its current base in New Orleans out to Baton Rouge, and Fudge’s stretches from its current Cleveland anchor down to Akron under. In both cases, potential challenges come as a direct result of these new constituencies.

The same goes for the districts held by Clay, Clarke and Jackson, while Richardson’s district was wholly redrawn by the independent California Citizens Redistricting Commission. Clay could face Rep. Russ Carnahan (D), Clarke will face Rep. Gary Peters (D), Jackson faces former Rep. Debbie Halvorson (D) and Richardson is being challenged by both a white member of Congress – Janice Hahn – and an African-American member of the state Assembly, Isadore Hall.

Redistricting expert David Wasserman of the Cook Political Report notes that almost all of these members have a district that is at least 20 percent new, and he said that was a conservative estimate for many of them.

Those watching these races closely suggest Clarke and Richardson are in the most trouble. That’s because Clarke is running against a good campaigner in Peters, and because Richardson has a lot of new territory and doesn’t have anything close to a majority-black district.

The rest will either face white members of Congress in heavily black districts or have the advantages of incumbency in most of the territory of their newly redrawn districts.

Still, many of them will be challenged by state legislators or politicians with names that are well-known in the black community. New York state Assemblyman Hakeem Jeffries and Greenville, Miss., Mayor Heather McTeer Hudson, who are running against Towns and Thompson, respectively, are both seen as rising stars in their states.

Black members of Congress have often faced primaries from ambitious up and comers in the past but very few have actually been unseated.

Rep. Cynthia McKinney (D-Ga.) lost primaries in 2002 and 2006, Rep. Al Wynn (D-Md.) was defeated in 2008, and Rep. Carolyn Kilpatrick (D-Mich.) lost in 2010. All were replaced by other black politicians (Clarke replaced Kilpatrick), but all gave their voters significant reason to unseat them — whether from a lack of effective constituent service or some personal problems.

“Unless there’s some scandal, they’re very, very rarely successful,” said David Bositis, an expert on racial politics at the Joint Center for Political and Economic Studies, about primaries to sitting African American members. “And they rarely have the amount of money that the CBC members have.”

At the same time, even CBC members with major personal and political problems have been returned to their seats by wide margins in the recent years, including Rep. Charles Rangel (D-N.Y.) in 2010 and then-Rep. William Jefferson (D-La.) in 2006.

Among those CBC members without major liabilities, very few have had any problems in the primary. Consider this: even President Obama was unable to unseat Rep. Bobby Rush (D-Ill.) in a 2000 primary, losing nearly two-to-one.

In the end, it’s unlikely many of these CBC members will lose, but the fact that many of them will face significant opposition is certainly unusual — and worth keeping an eye on in an environment in which voters are looking for change.