(CNN) The Pennsylvania 18th special congressional election between Democrat Conor Lamb and Republican Rick Saccone is finally here!

The good news for poll watchers, no matter your party affiliation, is it shouldn't be too late a night if the returns come in at the same rate they have in prior years. We should have a clear idea of who has won the race by 11 p.m. ET.

But when polls close at 8 p.m. and results are still coming in, surely the question will be asked: who is winning?

The best way to get at that question is to look at how each candidate is doing in each of the 18th District's four counties and compare that to county benchmarks based off of the past two presidential results.

One candidate may end up winning district-wide by greatly surpassing their benchmarks in one county, despite coming in under their benchmark in another. Still, they are a good starting point to making sense of the results.

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