Why did the networks take so long to call Wisconsin?

[TJ in Oregon]

Allegedly, I believe, they were waiting for absentee ballots to be counted in Milwaukee County, which provided Hillary somewhere around a 20,000 vote boost. I suppose it may have been possible for the boost to be larger, or that the networks were expecting 2012-type margins out of Milwaukee County and thus withheld judgment until it was obvious what the numbers would look like.

Another possible reason is that there were still a dozen or so precincts in Madison that had to report that are actually ghost precincts with <10 voters (I don't know why they exist but they do) but that the media could have mistakenly believed were similar to the more populous city wards, some of which gave Hillary up to ~2,000 vote margins.

As a local it was fairly obvious Wisconsin was over before midnight, but I suppose the national media was less convinced without paying close attention. (You can get the fastest results by checking the county clerks' websites most of the time; plus you can see which precincts are out). Plus it makes sense for the media to exercise a great deal of caution when calling critical states in presidential elections. Hey you never know, they may randomly forget to count Brookfield again.

I was starting to think Trump might win Wisconsin when Brown and Door Counties started coming in and his margins there were gigantic.