The decennial redrawing of congressional districts has forced members of the same party to square off during party primaries across the United States.
Soon after the U.S. Census released its population count and sent state officials scrambling to redraw lines, The Hill said the redrawn maps are forcing some longtime incumbents to run in unfamiliar and sometimes hostile territory.
While the member-on-member tilts won't determine control of the House of Representatives, they have disrupted friendships and undermined some alliances, The Washington Post reported recently.
And because the intraparty contests force voters to choose between representatives who could be polarizing or compromising -- in reconfigured districts where they don't have real relationships with their constituencies -- the direction of both the Democratic and Republican parties could be determined.
Witness what happened to Rep. Dennis J. Kucinich, D-Ohio, the two-time presidential candidate and emblem of the anti-war left, was handed a bruising defeat in Ohio's Democratic Party primary on Super Tuesday (March 6) by fellow incumbent and one-time ally Rep. Marcy Kaptur thanks to a Republican-drawn congressional map.
In a battle that drew cries of foul when House Republican leaders expressed their preferences, freshman Rep. Adam Kinzinger tripped up veteran Rep. Don Manzullo in Illinois.
Other incumbent-on-incumbent contests found Rep. Bill Pascrell Jr. ousting longtime friend, Rep. Steven R. Rothman in New Jersey, and Rep. Mark S. Critz besting Rep. Jason Altmire, a fellow conservative Democrat in Pennsylvania.
"These races tend to turn friends into enemies and bring out the worst in every political actor," said David Wasserman, an analyst with the non-partisan Cook Political Report. His research indicates the 2012 election cycle features more intraparty battles between incumbents than ever.
Thirteen House races this year pit incumbents against one another and of those contests 11 members of the same party are battling for their party nomination and the opportunity to return to the nation's capital.
In the coming weeks, at least four primary battles will match incumbents against each other, the Post noted.
In Arizona, one Aug. 28 contest features two freshmen who took office in 2010 as part of the Republican takeover of the House fueled by the Tea Party movement and anti-incumbency fever.
After a redistricting commission adopted a map favoring Democrats, GOP Rep. Ben Quayle, 35, had to choose between remaining in his now more politically balanced district -- and face potentially tough biennial re-election efforts -- or move into a more friendly district, setting up a primary challenge to fellow Republican freshman Rep. David Schweikert, 50.
Quayle calls the primary fight an "unfortunate situation," while Schweikert termed it it "a disastrous waste of resources," the Post said.
While some of the redistricting intraparty battles are the result of lines drawn by the controlling party in the statehouse or by non-partisan redistricting commission, others come to a matter of math -- legislative districts must be redrawn to accommodate shrinking, or growing, populations.
Michigan and Missouri had to redraw legislative maps to combine districts to accommodate smaller populations in Detroit and St. Louis metropolitan areas. Their primaries are on Aug. 7.
"I'd certainly rather be running against a Republican," Michigan Democratic Rep. Gary Peters said of his race against Rep. Hansen Clarke.
In the Show-Me State, Democratic Reps. William Lacy Clay and Russ Carnahan will face off in a realigned district that encompasses St. Louis and its northern suburbs.
In Florida, the philosophies of the Tea Party-influenced 2010 midterm elections also mark the Aug. 14 party primary race between Republican freshman Rep. Sandy Adams and House Transportation Committee Chairman John L. Mica, the Post said. Florida's population exploded, resulting in the creation of two seats.
"I think the question is: How do you expect someone who's been here and helped create the mess, to be the one to fix the mess that they helped create?" Adams said.
Mica has been taken to task by House conservatives -- Adams among them -- for helping to shepherd the long-term transportation bill that passed on a broad bipartisan vote. The 52 conservatives voted against it because it included too much spending.
"People want you to be advocates for the district, and I think I've been a strong advocate," he said.
The same anti-incumbent, pro-outsider attitude that fueled Republicans in 2010 was alive in several U.S. Senate party primaries, noted Larry Sabato, of the University of Virginia's Center for Politics in a recent column.
Tea Party-backed challengers have logged some memorable victories, notably Indiana Treasurer Richard Mourdock's defeat of veteran Sen. Richard Lugar, and state Sen. Deb Fischer, who battled from far back in the pack to knock off better-known opponents in Nebraska.
Mourdock's victory turned another typical re-election win by Lugar into a potentially hotly contested race in Indiana, Sabato said. Even though Indiana has moved back to the red after narrowly supporting President Obama in 2008, political observers aren't counting Democratic Rep. Joe Donnelly out completely.
Fischer, on the other hand, is expected to defeat former governor and one-time Sen. Bob Kerrey in November.
States losing congressional representatives were Illinois, Iowa, Louisiana, Massachusetts, Michigan, Missouri, New Jersey, New York, Ohio and Pennsylvania.
Picking up additional representatives were Arizona, Florida, Georgia, Nevada, South Carolina, Texas, Utah and Washington.