2016 State House CPI
2016 State Senate CPI
The updated Civitas Partisan Index (CPI) shows the political balance of power in North Carolina for the 2016 elections.
The CPI (Modeled after the Cook Partisan Voting Index developed for congressional districts) compares votes cast in each N.C. legislative district to votes cast in the state. The result is a letter (D or R) followed by a number, indicating the extent to which each district leans Democrat or Republican. For example, a district whose voters allotted five more percentage points to the Democratic candidates compared to the state average receives an index score of D+5.
Why? You ask, did we delay the rollout of the CPI after the 2016 General Election? The answer is simple – redistricting, of course! Just days after the 2016 election, on November 29, the U.S. District Court for the Middle District of North Carolina, in the case of Covington v. North Carolina, entered an order directing the defendants (N.C. legislature) to redraw legislative districts by March 1, 2017. Click here for a redistricting timeline.
Knowing that the legislative maps would change, we decided to wait until the dust settled to put together the 2016 CPI. It was a good thing, too, since the fight over North Carolina’s maps would rage on through 2017 and until the current maps were decided on by none other than the U.S. Supreme Court in February 2018.
The newest CPI took the 2016 Council of State vote totals (by precinct) and applied the numbers to the newly drawn legislative districts. Because many districts have changed in both the state senate and the state house, we can’t contrast all the individual districts in this CPI with the last one. However, we can compare average voting patterns from 2016 to those in 2012 and earlier. In the 2016 general election, 51.3 percent of the vote went to Republican Council of State candidates while 48.3 percent went to Democrats. In 2008, the numbers were nearly reversed, Democrats received 53.4 percent of the total votes for Council of State candidates compared to 46.6 percent for Republicans.
The CPI utilizes voter data from presidential election year results for governor and the other Council of State offices (i.e., lieutenant governor, commissioner of agriculture, commissioner of insurance, commissioner of labor, attorney general, secretary of state, superintendent of public instruction, state treasurer and state auditor). Although President and U.S. Senate election results are also available, state-level races give a more accurate picture of how voters will vote in a state legislative race than do national races.
While it does not predict elections, the CPI reveals which districts lean Republican or Democratic, and may illuminate significant trends. In using the CPI, it’s important to remember that elections featuring incumbents, the candidates’ traits and experience, the campaigns, fundraising and current political issues can play powerful roles.
History
In early 2008, the Civitas Institute premiered the North Carolina Partisan Index, now the Civitas Partisan Index, using data from the 2004 General Election.
In the 2008 CPI, of the 60 contested legislative seats, all but ten seats went to the dominant party as indicated by the CPI. (Three seats had a neutral CPI). Among the ten districts that were not in line with the CPI score, eight were in the range of R+3 to D+3, and most involved races with multi-term incumbents, well-known challengers, or significant spending differences between the candidates. The CPI model correctly predicted the outcome of all but one state House race, when the value of incumbency is taken into account.
Compared to the 2004 CPI model, the 2008 CPI showed a higher concentration of Democratic-leaning voters in the urban population centers. While voters in most of the state were somewhat more likely to vote for Republican statewide candidates in 2008 compared to 2004, voters in Buncombe, Cumberland, Durham, Forsyth, Guilford, Mecklenburg, and Wake counties favored Democratic candidates more heavily. In fact, 19 of the 21 state House districts that voted significantly more Democratic in 2008 compared to 2004 – districts whose CPI moved more than 3 points Democratic – were in those seven most populous North Carolina counties.
In 2010 a small adjustment was made to the 2008 House CPI after the state legislature passed a bill (House Bill 1621) to realign districts in Pender and New Hanover counties to comply with an order of the North Carolina Supreme Court, in Bartlett v. Strickland. The voter data remained the same – only the district lines changed. The changes were limited to House districts 16 and 18 and did little to impact the CPI data. House District 16 decreased from R+9 to R+8 while House District 18 remained D+12.
In 2010, Republicans became the majority in both the House and Senate in part by winning in 17 districts, held by Democrats, where the CPI indicated a majority of voters prefered Republicans. Also, Republicans won three more districts that held a neutral value. The seven districts won by the Republican candidates in 2010 that were not in line with the CPI score ranged from D+1 to D+4.
The CPI is not a predictor of future legislative contest outcomes, but it does give a glimpse of the voting tendencies within a district. It is a way to identify districts that swing, lean, or firmly trend towards one political party or the other. Many Council of State seats have been unevenly contested in the past, making it difficult to predict results “down ticket” looking at raw numbers alone. By looking only at deviations from the state average, the Civitas model can mitigate the effects of incumbency and uneven contests.
We invite you to check out your legislative districts on the CPI. You’ll get valuable insights on this year’s campaigns and elections.
