Published: Mar 31, 2014 5:06 AM EDT

ORLANDO, Fla. (AP) - Florida is a politically divided state. The Republicans have won the last four gubernatorial elections, but the Democrats have carried the state in the last two presidential elections. One U.S. senator is a Republican, while the other is a Democrat. The Democrats hold a slight edge in voter registration.
    
But that narrow divide becomes a chasm in Florida's congressional delegation and in the Legislature.  Sixteen of Florida's 26 U.S. representatives are Republicans, with one vacancy that will almost assuredly be filled by a Republican. Republicans also hold a 26-14 advantage in the Florida Senate and a 76-44 margin in the state House.
    
Some Democrats argue that the discrepancies are caused by "gerrymandering" -- the Republican-controlled Legislature drawing districts to give the GOP an unfair advantage, which would be illegal under Florida law.
    
But two political science professors say the discrepancies aren't so simple or nefarious - they have used the Sunshine State to popularize their argument that large concentrations of Democrats living in cities have given Republicans a redistricting advantage not just in Florida but nationwide.
    
Jowei Chen of the University of Michigan and Jonathan Rodden of Stanford University say no amount of reforms to eliminate gerrymandering is going to change an inherent bias based on where people live.
    
"Human geography plays a far greater role in generating electoral bias in the United States than commonly thought," they wrote in an influential 2013 paper.
    
Reformers in Florida have tried to stamp out gerrymandering. They successfully convinced voters in 2010 to approve two amendments to the Florida Constitution that would reduce the opportunities for lawmakers to make legislative and congressional districts that benefit one party over the other. The amendments require districts to be compact and contiguous whenever possible and to follow existing city and county boundaries. They also prohibit attempts to diminish the chances for minorities to elect a candidate of their choosing.
    
Chen and Rodden argue that Democrats tend to live in densely-populated cities while Republicans are more evenly scattered throughout suburban and rural areas. They also argue that Democratic precincts tend to be next to other highly-Democratic precincts, more so than Republican precincts, which tend to be located in politically-mixed neighborhoods.
    
As a result, Democrats tend to be tightly packed into fewer districts than Republicans. Republican-dominated districts tend to be more diverse than Democratic precincts since pro-Republican rural areas often include Democrats in small cities to reach the population threshold needed to create a district.
    
In Florida, this translates into highly-Democratic districts along Florida's southeastern coast in and around Fort Lauderdale, Miami and West Palm Beach. Meanwhile Democratic precincts in interior cities like Ocala, and college towns like Gainesville and Tallahassee, are swallowed up by more rural, Republican districts, essentially drowning out Democratic votes.
    
"When compact, contiguous districts are imposed on this geography without regard to partisanship, the result will be a skew in the distribution of partisanship across districts such that with 50 percent of the votes, Democrats can expect fewer than 50 percent of the seats, " Chen and Rodden wrote.
    
Despite having new redistricting standards in place, reformers felt the congressional plan illegally favored Republicans and incumbents and diminished the opportunities for minorities to elect representatives of their choice.
    
The reformers, led by the League of Women Voters of Florida, have sued the Florida Legislature to challenge the Senate and Congressional redistricting plans and to prevent the current districts from being used in any future elections. The lawsuit is pending, and the Florida Supreme Court ruled in December that legislators can be forced to testify in the lawsuit, setting aside a long-standing privilege that legislators usually enjoy.
    
Deirdre MacNab, president of the League of Women Voters of Florida, said the new amendments are giving voters more choices.
    
"With regard to the House seats, Floridians have already seen a significant increase in the numbers of competitive districts," she said.

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