Senate polls in individual states have moved around…but the Meta-Margin and the average seat count have stayed stable. Nonetheless, the crystal ball is cloudy. Why is that? The Midterm Polling Curse. Spoooooky!
As I wrote last week, everyone’s calculations are, to an extent, built on sand. Historically, in any given year midterm polls have been off in the same direction by a median of 2 or 3 percentage points. Depending on the year, either Democrats or Republicans end up outperforming polls. In current poll medians, six races are within less than 2 percentage points: Alaska, Colorado, Georgia, Iowa, Kansas, and North Carolina. Therefore all six of these races could be won by Republicans…or all six could be won by Democrats.
The other races total 48 Republicans and 46 Democrats/Independents. Republicans are slightly favored to take control, since an even split of the six close races would give them the 51 seats they need*. However, the likely possibilities range anywhere from a Republican majority of 54-46 to a Democratic majority of 52-48. As of today, cranking through the math and the uncertainties gives a probability of 55% for a Republican takeover.
I am thinking about how to guess on Election Night where in this range the race will land. I’ve decided that key races to watch are…Kentucky and New Hampshire. Wait, what?? Here is why.
The polls will be off, on average, by some amount in one direction or the other. Let’s call that average amount Delta. On Election Night, I will be watching returns carefully for clues about how large Delta is. In particular, I’ll be watching Kentucky and New Hampshire. Even though both races have a clear favorite, they have the advantage that voting ends fairly early in the evening. If either party outperforms polls in these states, that might indicate a broader trend nationwide.
First, here is a map of poll closing times, courtesy of Daily Kos Elections.
I should start with a major caveat. Initial returns will often be hard to interpret because within each state, sparsely-populated counties are likely to report earlier than densely-populated areas. Therefore, care is necessary in estimating the statewide vote accurately before all the votes are counted. The Huffington Post has a method for doing this. I’ll be doing something similar at Reuters headquarters on Election Night in New York City. Within permissible limits, I’ll share that information as the evening unfolds.
Here is the order in which I will be watching races. All times are Eastern.
6:00-7:00pm: Kentucky polls close. Mitch McConnell (R) has this race wrapped up, with a 6.0 ± 1.1% (median ± SEM) lead in opinion polls. If his actual lead is 8% or more, he is outperforming polls. If he wins by 4% or less, he is underperforming. The amount of over/underperformance is our first estimate of Delta.
7:00pm: New Hampshire, Florida, and Georgia. New Hampshire closes in most polling stations (some will stay open until 8:00pm). This small state counts fast. Currently, Jeanne Shaheen (D) leads Scott Brown (R) by 3.0 ± 0.7% and will probably win. If she wins by 1% or less, Republicans are likely to outperform polls in other states as well. Of course, if she loses, that presages an evening of wins for Republicans. On the other hand, if she wins by 5% or more, that’s a good sign for Democrats in other states.
Also closing (except for the panhandle) is Florida. In the governor’s race, Charlie Crist (D) currently leads Governor Rick Scott (R) by 1.0 ± 0.9% in opinion surveys. If Scott pulls out a win, that may indicate a good night for Republicans. However, we may not find out the answer until late in the evening, because Florida has late-reporting urban counties such as Miami-Dade.
Finally, the Georgia Senate race is currently tied (0.0 ± 0.9%). This one’s tough to use to calculate Delta, since it may be trending toward David Perdue (R). An alternative is to watch the governor’s race, where incumbent Nathan Deal (R) leads Jason Carter (D) by 3.0 ± 0.8%.
7:30pm: North Carolina polls close. Accurate estimation of the vote may be hard because the state has rural and urban areas. However, the race is basically tied, with Senator Kay Hagan (D) leading Thom Tillis (R) by only 0.5 ± 0.9%. So it’s an important one to watch.
8:00pm: Kansas polls close.
9:00pm: Colorado polls close.
10:00pm: Iowa polls close.
Midnight-1:00am: Alaska polls close.
*In addition to simple polling math, two additional issues may arise. First, if the Georgia Senate goes to a January runoff, this will have an unknown effect on voting. Normally, a runoff would favor Republicans because of lower turnout. But if Senate control hinges on such a runoff, turnout might be higher. Second, if Independent Greg Orman wins and the Senate is 50R, 49D/I, he has the option of caucusing with Democrats, who have aided him; or Republicans, who have attacked him at every turn. I am assuming he would choose the Democrats.