Official exit poll tabulations will be posted momentarily (as the polls close) at these links:
I'll live blog to the extent that news seems relevant in reverse chronological order, all times Eastern:
12:36 - Our comments section featured some speculation early this evening about the early exit poll estimates being wrong. The estimates were off slightly but with 99% of the precincts reporting, it looks like they were off in Clinton's favor. The current count shows Obama winning by a 22-point margin (60% to 38%) and more than 401,000 votes cast.
Two things I notice in the current exit poll tabulation (which may still update again by morning). First, make of it what you will, but Obama's 26% of the white vote was comparable to what he received from white voters in Alabama, Louisiana, South Carolina and Tennessee. Among the Southern states, only Georgia gave Obama more than 30% of the white vote.
Second, the open Mississippi Democratic primary -- the first to be held after John McCain secured his nomination -- included 2-3 times as many Republicans (12%) as the other states. And those Republicans supported Clinton by a 3-to-1 margin, far more than Republicans in any of the other Southern states.
11:07 - An update on turnout: I can't find a better source online, but this MyDD post from earlier today quotes a CNN story that put the total vote in the 1988 Mississippi Democratic presidential primary at "more than 359,000." The current Clinton-Obama vote total, according to CNN, is over 366,000 with 9% of the precincts uncounted (and Thatcher is ahead of me on this in the comments).
10:32 - In the comments, Thatcher notes:
all day long, they were saying that turn-out was light-to-moderate ... about 100K-150K voting ... yet we are over 240,000 now. No, it won't hit 1988 numbers - but what's up with the majorly wrong turnout prediction?
A quick Googling turns up an AP story that had the Mississippi Secretary of State, as of last night, "predicting a light to moderate turnout" of 125,000 to 150,000 today (emphasis added). So we are talking about a pre-election prediction, not an estimate based on actual turnout. What are these sorts of estimates based on? Who knows, but in my experience, this is not the first time that a Secretary of State's early prediction turns out to be wrong.
10:23 - An update in the exit poll tabulations shows the current vote estimate (which should by now be based mostly on random sample of actual results from randomly selected precincts) shows a margin of 56% Obama, 41% Clinton. That's pretty close to the current actual vote count (57% Clinton, 41% Obama with two-thirds of the precincts counted).
8:33 - 6% for Paul, not 62%. My bad.
8:30 - I just want to take a moment to apologize, again, for the comment posting bug that has frustrated everyone over the last month or so with error messages and caused inadvertent double (and sometimes) posts. In an effort to identify the bug, we made one small and very temporary change this afternoon that will allow most posts to go through without an error message (but unfortunately, only after a long delay of 60 seconds or more).
However some of you will get an error message saying your comment was not posted because of "too many comments submitted from you in too short a time." That message is in error - no one has been blocked! However if you see this message you will most likely need to repost your comment. I can't apologize for this enough. Please bear with us for a few more days and we'll get this ironed out (I promise...or your money back).
8:24 - The exit poll tabulations just updated. Mark Lindeman's extrapolations show no overall change in the estimated Obama lead (59% to 41%).
8:19 - MSNBC just called the state for Obama. Note that the networks did not call the race for Obama even though the estimate used to weight the official exit poll tabulations showed Obama with a 19 point lead. Looks like the decision makers at the networks felt they needed to see some actual count (or perhaps a more complete set of exit poll interviews) to increase their confidence before making a call.
8:15 - The initial racial composition numbers in the tabulations are 49% white, 48% black. The latter percentage is a 5-7 points lower in the five pre-election polls released over the last week. The preliminary estimate of vote by race shows Clinton leading 72% to 27%, while Obama leads among African Americans, 91% to 9%.
8:03 - As the first tabulations go up, our friend Mark Lindeman emails the overall estimates extrapolated from the tables: 59% Obama, 41% Clinton for the Democrats and 76% McCain, 13% Huckabee, 6% Paul for the Republicans.
Click here for the usual caveats on how these numbers are derived and how they improve over the course of the evening. Click here from my National Journal column last week on how the estimates at this point in the evening have sometimes been off in Obama's favor (although not in either Georgia or Tennessee).
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