Where are the missing Senate votes?

There’s an unusual math problem I’m having as I look at MPR’s election results.

Number of votes cast in the race for president: 2,910,488
Number of votes cast in the race for Senate: 2,888,891
Difference: 25,397

Twenty-five thousand Minnesotans voted for the top of the ticket and left the second race blank? It’s possible. But why?

(More calculations to follow)

(2:39 p.m.) The AP has a slightly different Senate total: 2,880,764. I believe the AP’s vote tallying is independent of the Secretary of State.

(2:52 p.m) The AP has 2,898,691 votes cast for president. That’s a difference of 17,927 votes. Still that’s quite different from what the Secretary of State has, leading one to believe the AP might be closer to accurate, except that the Secretary of State has 100% of the votes counted, and the AP still had precincts outstanding.

It’s also quite possible the AP numbers don’t include absentee ballots.

(3:06 p.m.) Not surprisingly, the biggest drop in votes is in Hennepin County (I’m using the AP figures at the moment) where the difference in votes cast in the two races was over 4,000.

Percentage-wise, the biggest drop was in Lake County (4%), followed by Houston (2%), Lake of the Woods (2%), Traverse (2%), Wilkin (2%) and Winona (2%). Sen. Norm Coleman won four of those six counties.

(3:27 p.m. ) In comments, people smarter than me say this is a normal thing. I downloaded the spreadsheet for the 2000 race – the last time we had a presidential contest and a Senate contest) and I get virtually no difference in the vote. In fact, I get that there was just 1 more vote cast in one race than the other. I may be making a mistake there so double-check the math.