Illinois and Texas have taken center stage in a redistricting battle that could have significant ramifications for the future makeup of Congress.
Republicans accuse Democrats of gerrymandering in Illinois, a Democratically controlled state where the GOP stands to lose as many as six House seats in the redistricting process. Democrats have hurled similar charges against Republicans in Texas, saying the four new House seats that redistricting creates marginalizes minority groups.
Both cases could end up in a legal battle in courts.
Partisan gerrymandering occurs when one party redraws district lines specifically to displace rival party members and put them in a new district with less favorable demographics.
For Democrats, Illinois -- President Obama's adopted home state -- is a prized possession, and represents a chance to win back the House next year.
"Illinois and particularly the suburbs of Chicago have always been a center of gravity in our path to retake the House majority," Democratic Congressional Campaign Committee head Steve Israel, D-N.Y., said at a Christian Science Monitor breakfast for reporters this week. "The map that was drawn there gives us some opportunities."
Texas, meanwhile, is the GOP's sacred cow. It stands to gain the most seats in this year's redistricting process, giving Republicans a significant edge in the House and the electoral college. It also presents a new opportunity for Republicans to attract the Hispanic vote.
Republicans say the Democrats' charge of gerrymandering in Texas is hypocritical, given their strategy in Illinois to throw four GOP lawmakers into Democratic districts and pitting two Republicans against each other.
"They tend to blend the political and the legal as it suits them," said Christopher Jankowski, president and chief executive of the Republican State Leadership Committee. "Yes, the Republicans politically will do what they can to help themselves but only within the extent permitted by the law."
"To me, it's intriguing that the Democrats are so aggressive in Illinois and in effect doing what they're complaining about in Texas," he added. "What they've done in Illinois, I admire in its audacity... [But] they forfeited their moral high ground."
Republican were initially considered to have a strong upper hand over Democrats in the redistricting process, which takes place every decade, after the Census numbers are released. Republicans took over at least 19 Democratically controlled state legislatures in November and gained more than 650 seats, according to the National Conference of State Legislatures.
The gains, however, haven't brought the kind of blessing that the GOP had hoped for. Indeed, in many states, it has pitted Republicans against each other. And in critical states such as Iowa and Ohio, they are actually losing seats because of population changes.
"It's going to be a wash," Israel said. "It is not the huge existential threat that Republicans made it out to be."
But Republicans are still confident that they ultimately stand to gain in the end.
"I don't think it's a wash. I think it's still a net advantage," Jankowski said. "The demographics favor us. It's moved from the Northeast into the South. Yes, they've moved into some of the bluer areas of the red states ... But from a Republican standpoint, that is an opportunity to compete for votes."
It's not just Democrats and Republicans jockeying for more seats and favorable districts. In many cases, redistricting has also pitted Republicans and Democrats against their own colleagues.
In Missouri, for instance, Democratic Rep. Russ Carnahan stands to lose his seat as the state loses one from its delegation and received little support from fellow Democrat Emanuel Cleaver, who is gaining a sizeable amount of liberals in his district.
The Texas map makes the demographics less favorable for longtime Republican congressman Ron Paul, a libertarian who is considered the father of the Tea Party movement but one who has often clashed with the state's Republican establishment.
Both parties will also be tested in California and Florida, where ballot measures have set new ground rules for redistricting that could provide direction for the rest of the country.
Californians passed a proposition last year that would put redistricting efforts in the hands of an independent bipartisan commission formed solely for the purpose of drawing congressional district lines. The commission is the first of its kind in the country, although it has already garnered its share of controversy for not being non-partisan.
In Florida, voters passed a constitutional amendment that keeps the power to draw district lines in the hands of the state legislature but sets a specific criteria that says boundaries that are drawn cannot favor any political candidate or party. Florida will gain two House seats because of population gains, and although the increase would've favored Republicans, the new law might dent that advantage.