A new report finds growing urban and minority populations that will affect redistricting and reapportionment in the Mountain West.

The geography of American politics is shifting, and this is especially true in the Mountain West. These six states – Arizona, Colorado, Idaho, Nevada, New Mexico, and Utah – are undergoing changes large and small as they rearrange their political representation in response to the latest Census figures. As they redistrict their state legislatures and reapportion federal representatives, the new political boundaries being formed in these states are largely the result of two trends: increasing demographic diversity and a growth in urban populations.

A new report from the Brookings Institution digs into these shifts to understand how populations are changing and how these changes will likely affect the outcomes of future political races. Author David F. Damore writes that in these six states, the boundaries are being reshaped by high rates of population growth, the geographic concentration of that growth in urban areas and the growing number of minority residents there. As a result, Democrats are likely to see more votes in many parts of these states – in both federal and state legislative races.

The region is home to the four states that experienced the largest percent population increases in the country between 2000 and 2010 – Nevada by 35.1 percent; Arizona by 24.6 percent; Utah by 23.8 percent; and Idaho by 21.1 percent. This growth has brought three new U.S. House of Representative seats to the region in Arizona, Nevada and Utah. Beginning with the 2012 election, the Mountain West will have 29 U.S. House seats and 41 Electoral College votes. This growth has gradually turned the region more Democratic, especially in Colorado, Nevada, and New Mexico, and to a lesser degree in Arizona.

Damore finds that much of this shift to the blue side of the spectrum is due to the heavy concentration of new growth in the urban areas of these six states and, not unrelated, their increasing minority populations.

The largest metro areas in four of these six states saw increases in their populations between 2000 and 2010.

The Las Vegas metro area, for example, is now home to three out of four Nevadans. The state’s minority population also increased by about 11 percent between censuses, bringing the non-white population to nearly 45 percent. Two-thirds of Arizonans live in the Phoenix metro area. Arizona’s minority population also increased from 36.2 percent in 2000 to 42.2 percent in 2010. The Albuquerque metro area now houses about 44 percent of New Mexicans. Nearly 40 percent of all Idahoans live in the Boise metro area.

Only Denver and Salt Lake City saw their metro populations dip in the 2010 Census. But both are still significant population centers. Metropolitan Denver is home to more than half of all Colorado residents, and metropolitan Salt Lake City is home to about 41 percent of all Utahns.

These shifts have both national and state-level implications. But as Damore writes, the ways these shifting concentrations and demographics play out in each state’s reapportionment and redistricting vary.

[M]apmakers across the region are afforded different degrees of latitude in how they go about doing their work. For instance, in Nevada and New Mexico, the residency of incumbents can be considered, while Idaho forbids it. Idaho allows for twice as much inter district population variation for state legislative districts as Colorado and New Mexico, and Idaho only allows state legislative districts to cross county lines if the counties are linked by a highway. Arizona and Idaho mandate that two lower chamber districts be nested within the boundaries of a state senate seat, while Colorado, Nevada, New Mexico, and Utah do not. Nevada also allows for multi-member member state legislative districts. Lastly, Arizona’s redistricting plans must be pre-cleared by the U.S. Department of Justice. While Arizona is the only state in the region subject to preclearance, protection of minority voting rights also has been a point of contention in prior redistricting cycles in New Mexico.

…The mix of small chambers, increased urbanization, and large geographic spaces means very large and increasingly, fewer and fewer stand-alone rural districts.

And though demographics are major drivers of political boundaries, much of the political reshaping of districts happens in the courts. In each of the Mountain West states, the two factors of politics and demographics combine in a variety of ways to reshape upcoming elections.

Arizona: The last redistricting effort heavily skewed votes toward Republican candidates, filling two-thirds of the state legislature with Republicans, despite having only slightly more registered Republican voters in the state. A similar move this time is less likely, writes Damore, but rural districts are likely to be consolidated or eliminated, giving Democrats a slight advantage urban areas. Damore predicts that Arizona will become the region’s fourth swing state in the near future.

Colorado: The state Supreme Court has upheld a redistricting map favored by the Democrats that keeps two safely Republican districts, one safely Democratic district and four districts where neither party has more than a 4 percent advantage. These four will likely create interesting elections in the coming years. In the state legislature, the state supreme court has upheld a set of maps widely seen to favor democrats.

Idaho: With a Republican-dominated political scene, Idaho’s redistricting was more about spatial issues than partisan ones. Damore calls them a “regional anomaly” because they both benefit the GOP but also are more urban than previous boundaries. More Republicans were pulled into formerly Democrat-heavy state legislative districts, while one of its House districts was dramatically reshaped to lose 50,000 people.

Nevada: The growth of Nevada and the urbanization of its population has heavily shifted political representation to the metropolitan Las Vegas area. Damore notes that of the 63 seats in the state legislature, 47 are either partially or completely located in Clark County, which is a democratic stronghold in a Red state shifting Blue.

New Mexico: Redistricting is still being ironed out in the courts right now, but because much of New Mexico’s growth over the past decade has been in Democratic Albuquerque and its suburbs, the new maps are likely to favor Democrats in the state legislature and in its three House seats.

Utah: Still heavily Republican, Utah’s politicians have remapped the four U.S. House districts to split up the largely Democratic urban center of Salt Lake City. In the clearest case of gerrymandering, each district will include parts of the urban center, but more of the rural fringe, favoring the Republicans. The state legislature tips the same way.

Overall, the trend is a decreasing rural influence, which tends to translate into a decreasing Republican influence. But as Damore notes, the region is home to a large number of nonpartisan voters, which will create a level of political uncertainty in upcoming elections, despite a growing urban influence. At least three states – Colorado, Nevada and New Mexico – can be expected to lean Democratic in the 2012 presidential election, and there’s a small chance that Arizona’s shifts may turn it blue this year. Idaho and Utah aren’t likely to swing in this election cycle, but as the demographics and concentration of voters change, the political geographies of these states could begin to shift as their neighbors in the Mountain West already have.

Top image credit: CREATISTA /

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