Following last Tuesday’s hotly contested San Diego City Council election for District 7, interest was piqued over the weekend when Friday’s count of late absentee and provisional ballots showed front-runner and Republican Scott Sherman’s portion of the vote tally slipping from about 51 percent to 50.59 percent.

With about 88,000 votes left to count across the county, it’s unclear what proportion of those remaining ballots are in the City of San Diego or even the 7th District, for that matter.

Yet, what’s clear is that it takes at least 50 percent plus one vote to secure an outright victory in the primary.  With Sherman’s margin at last count heading towards that magic 50 number – even if only for a day or two — twitter recently sprang to life with a few self-annointed mathematicians, including yours truly (although I’d say I’m more of a wannabe in the arithmetic department than an anointed one).

The second place finisher in the primary race, Democrat Mat Kostrinsky, has no chance of catching Sherman, since he’s trailing by more than 10 points. Yet, political watchers know if Sherman falls below 50 percent, a forced top-two finisher run-off with Kostrinsky in November is a different day, with what will be a much larger turnout than the likely plus thirty percent achieved last Tuesday (the 27 percent turnout initially reported is also going up as the outstanding ballots are counted).

With four Democratic and three Republican city council seats assured, it would be a bit of an understatement to say the balance of power rests with this race and the District 1 runoff between Republican Ray Ellis and Democrat incumbent Sherri Lightner.  The difference between a 6-3, or 5-4 leaning-one-way-or-the-other council makeup matters greatly when measuring both majority council votes and mayoral veto thresholds, especially also eying a Carl DeMaio and Bob Filner mayoral ho-down.

That said, it’s a busy Monday at the Registrar of Voters office, with both Kostrinsky and Sherman partisans on hand ensuring the quality and accuracy of the ballot counting process. If there were still chad, these nice folks would be hanging on every one.

So, what are the odds Sherman falls below the mark?  Inquiring minds want to know.

Local policy and statistical wonk Erik Bruvold did an analysis, indicating that if the remaining 88,000 ballots are proportionally distributed geographically, Sherman would have to get less than 47 percent of the approximate 5,165 remaining District 7 votes to end up with less than 50 percent of the overall vote. He says on Twitter, “No interim updates have shown him pulling less than that,” while also noting that since prior vote counts can be treated as samples, none of them show Sherman under 47 percent. “(It’s a) low chance this one would be,” referring to the last uncounted ballots.

Bruvold also mentions, “It’s a fun exercise in probability math.”

Speak for yourself, dude.

Another ballot count update is anticipated from the Registrar of Voters late today.

Political operatives — and mathematicians — will be watching closely.

This entry was posted on Monday, June 11th, 2012 at 3:18 pm and is filed under Blog Posts.