One of the side-effects of the move to all-mail balloting in Washington State is that, because ballots can be mailed right up to Election Day, we never know the final vote count on the night of the election.

That's a bummer for people who like a cliffhanger with a speedy resolution, and it's especially a bummer in King County, which, because of its large size, is in a position to swing a lot of statewide results (and, because of its proportionally large number of procrastinators, may not fully reveal which way it's swinging the election until the end of this week, or even the beginning of next week).

You say: Ack! So we won't know the result in our super-close race for governor on Tuesday night? What about R-74, the marriage equality measure? And I-502, the pot legalization initiative? Will we have to wait for those, too?

Enter numbers whiz Matt Barreto of the nonpartisan Washington Poll, who is promising to take tomorrow's 8:15 p.m. vote count announcement from King County (which will be King County's only vote count announcement of the night, and only a partial count at that); and then combine King County's results with the results from all the other counties (which should be closer to final counts, hopefully); and then run all those numbers through some fancy mathematical procedures; and then issue a projection in certain statewide races around 9 p.m. or so.


Here's how Barreto explains what he and his colleagues will be doing:

On Election Night, every single county will not only report the election results, but they will also give us a very strong hint of the final election results.

That is because every single county will provide an estimate of how many votes they have remaining to count. They will tell us how many they have processed so far, and given the estimates of 81% turnout by Secretary of State Sam Reed, we can forecast a reliable estimate of how many more ballots will be from each county. Historically, election data has shown that the Yes/No or Dem/Rep vote within each county is very stable from election night to the final tally. However, the smaller counties across our state have far fewer votes to count, and they can count their ballots more quickly on Tuesday, November 6th.

In contrast, King County is the slowest to count its ballots because of the overwhelming volume of ballots it has to count. What that means is that of the ballots not counted on election night—those that still remain to be counted on Wednesday, Thursday, Friday—a disproportionate share of those come from King County. In fact, many counties are done counting by Wednesday whereas King County continues to process and count ballots for a full week after the election.

In 2009, the Ref-71 margin on Election Night was 51.1% yes, however the final tally was 53.2%, an increase of over 2 points. This same trend has been found in every single election since 2006 that I have analyzed, with no exceptions, and it is entirely the result of King County having to count almost 900,000 ballots which takes a very, very long time.

We have to wait until every single county has posted their final counts on Tuesday night—but once all the data are in Tuesday night, we can very easily forecast what the final numbers will be.