An analysis by The Associated Press has found that partisan gerrymandering influenced the outcomes of numerous congressional and state legislative races across the country last fall, giving an advantage to Republicans. It's created to detect cases in which one party may have won, widened or retained its grip on power through political gerrymandering.
The state House went from a 71-49 Democratic majority in 1994 to an 81-39 Republican majority after the 2002 election when districts were redrawn by Republican lawmakers.
The analysis found that Virginia was among those states with Republican-skewed state House districts as well as congressional districts. Democrats won 37 of 65 House seats, theoretically five more than would be expected based on their statewide vote share. Idaho has only two districts, both of which were won by Republicans in November. Democrats lost four seats to Republicans.More news: Queen's Speech axed to make way for complex Brexit talks
Republicans, who held 106 state House seats after the 2010 elections, have fared even better under the new map. All had districts drawn by Republicans after the last Census in 2010. In Michigan and Wisconsin, for example, the partisan advantage gained by gerrymandering was unlikely to occur by chance, according to a separate analysis AP commissioned from the Princeton University Gerrymandering Project.
Under a redistricting plan approved in 2012, Idaho's House seats are divided among 35 districts each district has two House seats and one Senate seat.
According to the AP data, even though House Republicans averaged 57.6 percent of the vote in the 100 districts across in in 2016, they won or retained 70 seats in the House of Representatives.More news: Gianforte to enter plea in assault case
AP also found that the drawing of districts for hundreds of US and state legislative districts gave Republicans a real advantage.
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.
The AP analyzed the 2016 election results using an "efficiency gap" formula developed by University of Chicago law professor Nick Stephanopoulos and researcher Eric McGhee of the nonpartisan Public Policy Institute of California. Their mathematical model was cited last fall as "corroborative evidence" by a federal appeals court panel that struck down Wisconsin's Assembly districts as an intentional partisan gerrymander in violation of Democratic voters' rights to representation.More news: Heads up...eyeing two systems in the tropics
Republicans controlled both MI legislative chambers and the governor's office when the maps were redrawn in 2011. That results in a 47 percent efficiency gap heavily favoring Democrats, but both races were close, and if fewer than 5,000 votes had switched in either district, the efficiency gap would be almost even.