State Polls and the Shadow States

Many readers have observed that the election of our next president will be decided not by a national popular vote, but by the states and the District of Columbia in the Electoral tally. The problem with the states as they relate to opinion polling, is that while the national polls have some points of concern, the state polls are relatively even less certain. The folks at Real Clear Politics show forty-nine different polling groups which have published results for states since the end of August, and few of these have publicly-released verification of their methodology, let alone access to their internal data. Caveat Emptor indeed , in these waters!

Even so, such information as has been presented can serve a purpose, to address curiosity if nothing else. I have reviewed and collated the information presented by RCP, and once again it is all here at the link if you want to do the same yourself. I would warn the reader that an average of polls is not statistically valid, but it does satisfy a certain curiosity. More, while there is a range of opinion among the pollsters, it is interesting to see how many polls were done for a given state. So, in the interest of public service, I am posting here a reference for the current polling average, along with the historical average since 1988, and the statistical trend for the state over the last 20 years. Please also note the columns for undecided, “Clear” and “Polls”, which will be explained below the report:

State (historical adv, trend adv) poll avg. (undecided) Clear? # polls
Alabama (h R+15, t R+32) 59.7-36.0 McCain (4.3 und) Clear, 3 polls
Alaska (h R+22, t R + 20) 57.7-35.0 McCain (7.3 und) Clear, 3 polls
Delaware (h D + 7, t D + 4) 43.3-56.0 Obama (0.7 und) Clear, 3 polls
Illinois (h D + 10, t D + 9) 37.7-55.0 Obama (7.3 und) Clear, 3 polls
Kentucky (h R + 8, t R + 21) 55.0-38.7 McCain (6.3 und) Clear, 3 polls


Michigan (h D + 4, t D + 2) 43.9-47.9 Obama (8.3 und) Unclear, 14 polls
Ohio (h R + 2, t R + 1) 46.4-45.4 Mccain (8.1 und) Unclear, 14 polls
Florida (h R + 5, t R + 9) 46.8-45.6 McCain (7.5 und) Unclear, 13 polls
Pennsylvania (h D + 6, t D + 2) 43.2-48.6 Obama (8.2 und) Unclear, 11 polls
Virginia (h R + 9, t R + 9) 47.0-46.7 McCain (6.3 und) Unclear, 10 polls
New Hampshire (h R + 3, t D + 2) 45.4-47.3 Obama (7.4 und) Unclear, 8 polls
New Jersey (h D + 6, t 0.0) 42.0-49.6 Obama (8.4 und) Unclear, 8 polls
Colorado (h R + 4, t R + 2) 45.1-48.9 Obama (6.0 und) Unclear, 7 poll
Indiana (h R + 14, t R + 21) 47.3-45.0 McCain (7.7 und) Unclear, 6 polls
Iowa (h D + 5, t R + 1) 41.8-51.0 Obama (7.2 und) Unclear, 6 polls
Minnesota (h D + 8, t D + 5) 44.5-48.8 Obama (6.7 und) Unclear, 6 polls
North Carolina (h R + 9, t R + 11) 49.3-45.2 McCain (5.5 und) Unclear, 6 polls
Oregon (h D + 5, t D + 7) 40.5-48.2 Obama (11.3 und) Unclear, 6 polls
Wisconsin (h D + 4, t D + 3) 44.2-47.8 Obama (8.0 und) Unclear, 6 polls
California (h D + 9, t D + 9) 39.4-51.8 Obama (8.8 und) Unclear, 5 polls
Georgia (h R + 10, t R + 17) 52.3-42.3 McCain (5.5 und) Unclear, 4 polls
Missouri (h R+ 2, t R + 9) 49.0-45.8 McCain (5.3 und) Unclear, 4 polls
Nevada (h R + 5, t R + 1) 46.3-46.3 tie (7.5 und) Unclear, 4 polls
New Mexico (h D + 2, t R + 1) 43.8-50.3 Obama (6.0 und) Unclear, 4 polls
Washington (h D + 8, t D + 9) 42.8-48.8 Obama (8.5 und) Unclear, 4 polls
Maine (h D + 8, t D + 18) 42.7-50.3 Obama (7.0 und) Unclear, 3 polls
New York (h D + 18, t D + 13) 40.3-52.7 Obama (7.0 und) Unclear, 3 polls
North Dakota (h R + 18, t R + 25) 49.3-41.3 McCain (9.3 und) Unclear, 3 polls
West Virginia (h D + 3, t R + 14) 48.0-42.3 McCain (9.7 und) Unclear, 3 polls
Connecticut (h D + 9, t D + 4) 39.5-53.5 Obama (7.0 und) Unclear, 2 polls
Idaho (h R + 27, t R + 35) 60.0-29.0 McCain (11.0 und) Unclear, 2 polls
Kansas (h R + 16, t R + 26) 55.5-39.5 McCain (5.0 und) Unclear, 2 polls
Montana (h R + 12, t R + 14) 53.0-41.0 McCain (6.0 und) Unclear, 2 polls
Oklahoma (h R + 15, t R + 35) 64.0-32.0 McCain (4.0 und) Unclear, 2 polls
Rhode Island (h D + 19, t D + 13) 34.5-54.5 Obama (11.0 und) Unclear, 2 polls
South Carolina (h R + 12, t R + 17) 54.5-42.0 McCain (3.5 und) Unclear, 2 polls
Utah (h R + 32, t R + 46) 63.0-28.0 McCain (9.0 und) Unclear, 2 polls
Vermont (h D + 13, t D + 26) 36.0-57.5 Obama (6.5 und) Unclear, 2 polls
Wyoming ( h R + 25, t R + 36) 57.5-37.5 McCain (5.0 und) Unclear, 2 polls
Arizona (h R + 8, t R + 14) 59.0-38.0 McCain (3.0 und) Unclear, 1 poll
Hawaii (h D + 15, t D + 3) 27.0-68.0 Obama (5.0 und), Unclear, 1 poll
Louisiana (h R + 3, t R + 17) 55.0-40.0 McCain (5.0 und) Unclear, 1 poll
Maryland (h D + 11, t D + 10) 37.0-60.0 Obama (3.0 und) Unclear, 1 poll
Massachusetts (h D + 23, t D + 23) 39.0-55.0 Obama (6.0 und) Unclear, 1 poll
Mississippi (h R + 14, t R + 19) 55.0-37.0 McCain (8.0 und) Unclear, 1 poll
South Dakota (h R + 13, t R + 20) 54.0-37.0 McCain (9.0 und) Unclear, 1 poll
Tennessee (h R + 5, t R+ 19) 55.0-39.0 McCain (6.0 und) Unclear, 1 poll
Arkansas (h D + 1, t R + 11) no polls, Unclear
Nebraska (h R + 24, t R + 34) no polls, Unclear
Texas (h R + 13, t R + 22) no polls, Unclear
District of Columbia (h D + 75, t D + 82) no polls, Unclear

Only five states are statistically clear at this time. The reason is what I call ‘the shadow’. That is, given the number of people interviewed for each of these state polls, the statistical margin of error is about +/- 4.0 percent. That means that McCain or Obama could each be as much as 4.0 points higher or 4.0 points lower in support than the results of the poll indicate, assuming the poll is valid as defined by the NCPP. This creates an 8.0 point range of uncertainty. The 8 points for the margin of error, when added to the undecided portion of the vote, gives the range of shadow. If the leader does not have a lead greater than the range of shadow, the poll is unclear. Also, if there are fewer than three polls performed on a state, the stated results are inconclusive, which is why some states with large leads for one candidate are still statistically “unclear”.

This is what I mean by the state polls not being very helpful. And to make matters worse, this aggregation does not remove outliers, and of course when there are only two or three polls for a state, it’s impossible to know which numbers would be outliers for a state.