How do they project a winner?

[julialnyc]

I'm very confused how they are calling certain races with small percentages in while not with others with larger percentages. I know some are by larger numbers, but some (like CT) I can't imagine were total blow-outs.

[texpatriot2004]

1. kick it out of curiousity nm

[Rufus T. Firefly]

2. It's a statistics thing.

They pull from random precincts and some such thing. I took PoliSci stat so long ago I don't remember the details, but it made perfect sense at the time I learned it.

[theothersnippywshrub]

3. Among other things, they look at overwhelmingly partisan precincts.

For example if an incumbent has historically carried certain precincts with over 80%, but this year carried such precincts with only 60% while the opponent is maintaing or increasing a historical advantage in other precincts, the political "experts" feel confident that the incumbent is going to lose.