If, over the long run, we expect Franken to win 51% of corrected ballots, his odds of winning the recount may be quite strong — in fact, he may be the prohibitive favorite depending on the number of recounted ballots.

UPDATE: Silver has already revisited this in a new post. His adjusted take on the situation: 

I hesitate to say this, but I think the evidence points on balance toward Franken being a slight favorite to win the recount.

UPDATE: In yet another installment, Silver says what we already knew: It’s a tie. 

 It is very, very close. 

A lot rides on the margin between Franken and Coleman staying small when votes are certified today, and on the belief, buttressed by exit polls, that under-counted ballots will break for Franken. Yet when he appeared Nov. 3 on MSNBC’s “Countdown with Keith Olbermann,” Silver didn’t put much stock in exit poll data:

Olbermann: Nate, when the exit polls leak out tomorrow … is there anything that you actually want to look at, anything that’s an actual valid indicator, or should you just throw them out as they come in?
Silver: No, totally throw them out. These things are not anything they’re cracked up to be. They’ve had a Democratic lean for years and years.

Silver may have been dissing exit polls’ utility in predicting election results, however, not in conducting after-the-fact demographic analysis.

In any case, it’s the kind of in-depth analysis Silver lavished only on select candidate preference polls during the heat of the campaign season. Now that it’s all over but the counting in a few places like Minnesota, the former baseball stats geek is apparently able and willing to turn his full mental powers on an individual non-presidential race to produce an at-length interpretation that leaves his readers’ heads spinning. “Swear to God, Nate, you’ve broken my brain with this one,” writes one. ”My goodness Nate — do you ever sleep? You need to get out more,” advises another. Adds someone named Bob: “Your sadistical analsis [sic] leaves me stunned.”

Some of the reasons (there are 10 in all):

1. Exit polls have a much larger intrinsic margin for error than regular polls. This is because of what are known as cluster sampling techniques. Exit polls are not conducted at all precincts, but only at some fraction thereof. Although these precincts are selected at random and are supposed to be reflective of their states as a whole, this introduces another opportunity for error to occur (say, for instance, that a particular precinct has been canvassed especially heavily by one of the campaigns). This makes the margins for error somewhere between 50-90% higher than they would be for comparable telephone surveys.

2. Exit polls have consistently overstated the Democratic share of the vote. Many of you will recall this happening in 2004, when leaked exit polls suggested that John Kerry would have a much better day than he actually had. But this phenomenon was hardly unique to 2004. In 2000, for instance, exit polls had Al Gore winning states like Alabama and Georgia (!). If you go back and watch The War Room, you’ll find George Stephanopolous and James Carville gloating over exit polls showing Bill Clinton winning states like Indiana and Texas, which of course he did not win.

3. Exit polls were particularly bad in this year’s primaries. They overstated Barack Obama’s performance by an average of about 7 points.