Swing States: Basic Math

The conventional wisdom is that in presidential elections two thirds of the states are so one-sided that they are irrelevant except for fund-raising. Most polling is done at a national level which doesn’t mean much, and there are varying opinions about the prospects for each of the swing states. How to think about the math?  Here are a few tools:

1. Charlie Cook’s Partisan Voter Index, or PVI. The premise is that each state has a predictable spread above or below neutral, and that by taking the national Obama/Romney result and overlaying it on each state’s traditional bias you can get a projection of how the national result would impact each of the swing states. As a starting point there are 14 states with 171 electoral votes with a history of being within a plus or minus four range, with the rest being irretrievably red (181) or blue (186).

2. Sean Trende recently wrote a great article on Real Clear Politics providing the PVI for most states for each of the last eight presidential elections, drawing a trend line for each. Some, like coal-based West Virginia, have moved significantly Republican; others, like Illinois have gone in the opposite direction. The electoral votes and PVI’s (with a + meaning advantage Republican) for the middle 14 “swing” states are:

Colorado (9)                    +0

Florida (29)                     +2

Iowa (6)                          -1

Michigan (16)                  -4

Minnesota (10)                   -2

Missouri (10)                   +3

Nevada     (6)                      -1

New Hampshire     (4)          -2

New Mexico     (5)               -2

North Carolina     (15)         +4

Ohio       (18)                        +1

Pennsylvania     (20)            -2

Virginia     (13)                   +2

Wisconsin     (10)                -2

3. 270 to Win offers an interactive map which allows the reader to designate the winner in each state, showing the overall outcome. In the case of a national tie in voter totals and assigning the above PVI values to the swing states, Romney would have 266 electoral votes (the base 181 plus 85), Obama would have 263 (the base 186 plus 77), and Colorado’s 9 would be a toss-up. A national plus 1% in either direction or movement of a single swing state in either direction would mean victory. It is that close.

Adding some subjectivity, it is hard to be optimistic about the states with large, growing Mexican-American populations (Colorado; Nevada; New Mexico), Romney must win Ohio and Florida, and has reason to be optimistic about Wisconsin (Scott Walker), New Hampshire (vacation home; neighbor), and Iowa (gay marriage). On Obama’s side it is hard to see him winning without Pennsylvania; he should carry Michigan (auto bailout); and Virginia (layoff threat to the DC suburbs). With that, plus Minnesota (Democrat) and Missouri (Republican) reverting to form, the outcome would be… da da da … Romney 273, Obama 265. A piece of cake.


For those who missed it, here’s the video of the president of the South Carolina AFL-CIO  explaining her opposition to the pro-business policies of Governor Nikki Haley. Imagine the media outrage if the tables were turned.