The formula is created to detect races where one party might have won or retained seats in the legislature through drawing district lines favorable to the party in power.
The analysis showed that Idaho is among the top 10 states in the country with the biggest "efficiency gap", or the percentage of seats won by Republicans beyond what would be expected based on their statewide average share of votes.
A nationwide analysis by The Associated Press shows lawmakers can cause some statehouses to skew more Democratic and others more Republican by redrawing political boundaries to cluster or divide certain groups of voters.
The analysis found that Virginia was among those states with Republican-skewed state House districts as well as congressional districts.
But "part of it is the gerrymandering issue, in that districts are simply drawn in such a way that it is very difficult" for Democrats to win in many parts of the state, Beatty added. At the time, Democrats controlled the House while Republicans controlled the Senate.
Republican critics of Democratic concerns over gerrymandering point to what they say is Democrats' poor campaigning, their concentration in cities-a sort of "voluntary gerrymandering", some say-and their lack of incumbents to explain the Republican voting advantage.
AP also found that the drawing of districts for hundreds of USA and state legislative districts gave Republicans a real advantage.
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British driver Jolyon Palmer did just that, bringing the red flag out and briefly halting the session midway through. His subsequent lap time gains put him in the 1m43s margin and he ended his first run with a best lap of 1m43.894s.
Republican House candidates received 763,824 votes in 2016, compared to 694,720 votes for Democratic candidates. The majority and minority party leaders in each legislative chamber each select one person to serve on the commission; the state chairmen of the Republican and Democratic parties also each select a commissioner.
The efficiency gap model was developed by University of Chicago law professor Nick Stephanopoulos and Eric McGhee, of the nonpartisan Public Policy Institute of California. Despite operating under the bipartisan system since 1992, plans can get caught up in lengthy legal battles before settling on new district boundaries. Nevada's districts were decided by a court, but Republicans complained at the time that they appeared more favorable to Democrats.
The AP used their method to calculate efficiency gaps for all states that held partisan House or Assembly elections for all of their districts in 2016. The efficiency gap scores show Republicans picked up at least two excess seats each in MI and North Carolina.
For Democrats to complain of gerrymandering is "pure nonsense", said Matt Walter, the Republican committee's president.
"The Democrats don't know how to run campaigns; they're frightful at it", he said.
"That's just a baseless supposition to blame that all on line-drawing", he said.
Calculating partisan advantage will take on new importance when the U.S. Supreme Court considers whether Wisconsin's state Assembly district maps violate Democratic voters' constitutional rights.