Why Ohio? The Numbers Don't Lie (Bellwether States Revisited)

Talk about bellwethers: Ohio's vote for the winning presidential candidate has deviated from the national vote an average of just 2.2 points since 1900 and only 1.3 points since 1964

As the number and definition of battleground states seems to fluctuate in the 2012 election cycle, sometimes a shorthand is introduced - a bellwether - which becomes the state to watch in the Romney vs. Obama matchup this November.

Of course, the definition of even a bellwether state is subject to interpretation.

Nevada, for example, has voted for the winning presidential candidate more than any other state over the last 100 years at 24 of 25 elections, although Ohio has the longest current streak at 12 consecutive cycles.

Missouri, meanwhile, leads the nation with the largest number of narrowly-decided presidential races over the last century, with Wisconsin and Pennsylvania close behind.

One of these states, however, has a leg up when it comes to not simply picking presidents, but doing so by a closer margin to the nationwide vote than any other.

A Smart Politics analysis of presidential election data since 1900 finds that Ohio's vote for the winning presidential candidate has averaged just 2.2 points off the national vote over these 28 cycles and deviated just 1.3 points since the Election of 1964.

Ohio has been a model in consistency when used to take the pulse of the national electorate over the decades.

During the 108 years of presidential elections since the turn of the 20th Century through 2008, the Buckeye State's vote for the winning candidate has been less than four points off the national vote in 25 of 28 cycles, and less than two points in 16 contests.

The only stretch in which Ohioans deviated modestly from the nationwide vote was a three-cycle stretch in 1924 (with a 4.3-point difference), 1928 (6.7 points), and 1932 (7.5 points) - although each of these cycles fell below the 28-cycle statewide average differential of 8.3 points across all 50 states.

Since 1964, Ohio has been particularly prescient - not only for being the only state in the nation to back the winning candidate in every cycle during this span, but also voting for the president within 1.3 points of the national vote across these 12 cycles.

The Buckeye State came within 1.8 points of the national vote in 1964, 1.8 points in 1968, 1.1 points in 1972, 1.2 points in 1976, 0.7 points in 1980, 0.1 points in 1984, 1.6 points in 1988, 2.8 points in 1992, 1.8 points in 1996, 2.1 points in 2000, 0.1 points in 2004, and 1.5 points in 2008.

While Ohio's presidential vote was frequently not the closest vis-à-vis the national vote across many of these elections, no other state can match how it consistently mirrors the national vote from cycle to cycle.

Coming in second over the last century is the State of New Mexico - which participated in its first presidential election in 1912 - clocking in at an average of 2.3 points off the national vote for the winning candidate.

New Mexico has a nation best four cycles since 1900 in which its vote for president was the closest to the nationwide vote: in 1944, 1972, 1996, and 2000.

Ohio (1948, 1984, 2004) and Delaware (1908, 1940, 1964) achieved this distinction three times each, with California, Missouri, and Virginia doing so two times, and Florida, Iowa, Maryland, Michigan, Minnesota, Montana, Nevada, New Hampshire, New Jersey, Oregon, Pennsylvania, and Washington doing so once.

Number of Cycles in Which State Vote for Winning Presidential Candidate Is Closest to Nationwide Vote, 1900-2008

The (currently solid blue) State of Delaware has been the third most accurate bellwether state for determining the national vote for president over the last 28 cycles at just a 3.0-point deviation, although it has slipped in recent elections.

Over the 25 elections from 1900 to 1996, Delaware's vote for the winning candidate deviated from the nationwide vote by 5 or more points just three times (in 1928, 1932, 1936). It has done so three out of three cycles already in the 21st Century: by 6.0 points in 2000, 5.0 points in 2004, and 9.0 points in 2008.

Rounding out the Top 10 states are Missouri at #4 (3.2-point deviation), Illinois at #5 (3.3 points), California at #6 (3.4 points), New Jersey at #7 (3.5 points), Oregon at #8 (3.7 points), and Washington, Colorado, and West Virginia at #9 (3.8 points).

Southern states largely populate the Bottom 10 on this list - not a surprise given the region's steadfast vote for Democratic candidates regardless of the national winds for several decades under the period under analysis.

Mississippi owns the greatest spread from the nationwide vote at 27.2 points, followed by South Carolina at #49 (25.3 points), Alabama at #48 (20.2 points), Georgia at #47 (18.7 points), Louisiana at #46 (18.4 points), Texas at #45 (14.6 points), Arkansas at #44 (12.6 points), Vermont at #43 (11.8 points), Florida at #42 (11.7 points), and Utah at #41 (9.7 points).

Average Difference in Vote for Winning Presidential Candidate and Nationwide Vote, 1900-2008

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