A new analysis of population changes since the 2010 Census by the University of North Carolina Population Center suggests that by the next census in 2020 seven southern and western states are poised to gain at least one seat while nine states in the Midwest and Northeast are likely to lose at least one seat. (Seat gains and losses are a determined by a decennial reapportionment of the nation's population based on the ideal number of people that should be in each of the 435 congressional districts; in 2010 that number was 710,767 people)
Arizona, California, Colorado, Oregon, Florida, North Carolina, Texas, and Virginia could all gain at least one seat in the four different scenarios UNC ran in trying to assess what the map will look like after the 2020 Census. Illinois, Michigan, Minnesota, Ohio, New York, Pennsylvania, Rhode Island and West Virginia are expected to lose at least one seat. (For a full explanation of the data UNC used to run its simulations, check out their full write-up of the results.)
Texas continues to be the fastest growing state in the country. Based on 2014 population estimates, the Lone Star State has already grown enough to add a 37th congressional district and may well add two more by the 2020 Census. At 39 House seats, Texas would be the second largest House delegation behind only California, which is projected to have 54 districts by 2020. The growth in both of those states over time is remarkable; in 1910, California had just 11 congressional seats while Texas had 18. While California's growth has stagnated somewhat in the last few decades (it had 52 House districts in 1990), Texas is booming; if the UNC projections bear out, it will have added seven congressional districts from just 2000 to 2020.
On the other end of the spectrum, the Rust Belt and the Northeast continue to fade in terms of political power in Congress. In 1970, Ohio had 23 members of Congress and New York had 39. Based on the UNC projections, Ohio will have just 15 House districts after 2020 while New York will have just 26. Michigan is set to lose its sixth congressional district in the last five decades; Illinois is projected to lose its seventh in that same time frame.
The near-term effect of these population changes is that delegations from Texas, North Carolina, Arizona and Florida will become larger and more powerful within the halls of Congress. While the leader of House Republicans, Paul Ryan, comes from Wisconsin — a Midwestern state — the fact that the large and growing delegations are in the West and South means that their priorities will get a more prominent hearing from the party leadership.
The longer term impact is a likely shifting of the presidential battleground southward and westward. Electoral math dictates that the candidates will go where more electoral votes are available. And that will increasingly be in places like Arizona, North Carolina, Colorado and Virginia. Fun fact: Assuming the UNC projections are accurate, North Carolina (16) and Ohio (17) will be almost equal in electoral votes by 2020.
That shift should help Republicans since the West and South have traditionally been more friendly to their side than the Midwest and the Northeast. But, Republicans' problems in winning the Hispanic vote in recent years, an issue potentially exacerbated by GOP presidential front-runner Donald Trump's rhetoric on immigration, badly complicates those potential gains given that much of the population increases in those regions come from the Latino community.
All of which makes it even more clear — and it was pretty damn clear already — why Republicans need to solve their Hispanic problem. And soon.