Margin of Error, Margin of Victory

Most of the national polls that survey the Presidential election race use samples that have a margin of error of 3.0-3.5 points. That means when you see a poll result that shows a 47-47 tie, either number could deviate by that amount. Therefore, a 47-47 tie could actually be 50-44 in favor of one of the candidates.

Almost all of the national polls are now within the margin of error so we appear to be heading to another close election.

I thought it might be useful to review the states that were within a 7% margin in 2012 as we head into the final days before Election Day. These are the states that have the greatest potential to change this year since they had the tightest victory margin last time.

Elections are won at the margin. If a candidate can turnover a vote that was for the opposing party the last time around, they get a double advantage in the final tally. Thus, a voter for Obama in 2012 who changes their vote to Trump this year, reduces Clinton's vote by one and increases it by one compared to what Romney did in 2012. If 1% of voters in a state do this it actually produces a 2% effect in the margin.

Turning over a voter is much more powerful than merely finding a new voter. A new vote merely adds a vote but does not subtract one from the other side relative to the last election. To have the same effect in the final margin, you need to find two new voters for every one you turn.

With that background, let's look at the states that Romney won by a margin of 7% or less in 2012. Electoral votes are shown by each state.

North Carolina (15)  +2.04%

That's right, there was only one state that Romney won that he did not carry by at least 7%

These are the states that Obama won by less than 7%. It is a much longer list.

Colorado (9)            +5.37%

Florida (29)              +0.88%

Iowa (6)                   +5.81%

Nevada (6)               +6.68%

New Hampshire (4) +5.58%

Ohio (18)                  +2.98%

Pennsylvania (20)     +5.39%

Virginia 13)               +3.87%

Wisconsin (10)          +6.94%


Romney won 206 electoral votes out of the 270 that he needed in 2012.

How does Trump find his margin of victory in 2016?

First, he clearly needs to hold North Carolina as Romney did in 2012. Obama won the state in 2008 with a margin of just 0.3%.

Starting from Romney's base of 206, Trump needs to add 64 electoral votes to become our next President.

Winning Florida and Ohio would give him 47. He still needs 17 more.

Pennsylvania is the easiest route to get him there with its 20 electoral votes

Failing that, he needs to put several states together.

Looking at 2012, you would think Virginia should be winnable but the DC suburbs in Northern Virginia are affluent because of the establishment in Washington. Donald Trump is their worst nightmare. In fact, a recent poll indicated that 27% of federal government employees said they may quit if Donald Trump becomes President. The same for the lobbyist crowd. If you wonder how much power the federal bureaucracy has, look no further than the vote totals from Northern Virginia on election night.

Looking at the numbers, you see why Trump has been in Colorado, Iowa and Nevada so much and why he plans to have his final rally in New Hampshire.

Trump may also have an outside chance in Minnesota (+7.69% for Obama) and Michigan (+9.50%). It would still only take a net of 1 out of every 20 voters to turn from Obama to Trump to turn those states in his favor.

All in all, the margin of error in current polls suggests that the margin of victory in this election is going to be marginal whoever wins.