"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.  

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