By Dana Kozlov

CHICAGO (CBS) — Outside of Illinois, there are a half a dozen states that could decide this presidential race, including our neighbors to the north in Wisconsin.

CBS 2 Political Investigator Dana Kozlov explains why.

A reason Wisconsin could be so critical this year is because of how narrowly President Donald Trump won the state in 2016, by just under 24,000 votes, or less than one percent of the total vote, in large part because of how many counties went from blue to red.

Also From CBS Chicago:

Twenty-three of Wisconsin’s 72 counties flipped in 2016, and all of those swing counties flipped from voting for President Barack Obama in 2012 to voting for President Trump in 2016.

No Wisconsin counties flipped the other way.

In eight of those counties, President Trump won by just a small voting margin compared to the number of votes President Obama got  in 2012.

For instance, in Kenosha County, President Obama won by about 10,000 votes in 2012.  President Trump won Kenosha County by just 109 votes in 2016.

So Kenosha is one of eight counties that could flip back, and based on vote totals from four years ago, that could potentially swing Wisconsin right back into the blue.

Other than those swing counties, three counties around Milwaukee could also be key.  While all three are traditionally red, President Trump did not do as well in those counties as Mitt Romney did in 2012.  So, if his support there wanes, that could be key, because those are heavily populated counties and could translate into thousands of votes. If President Trump’s support increases, or voter turnout is bigger, that could really help him.

So will we know Wisconsin’s winner tonight? There is a big chance we won’t, for several reasons.

One of them is the sheer volume of absentee ballots.  More than 2 million were requested in a state which typically sees about 3 million voters in a general election.

And in several areas, including Milwaukee, those absentee ballots are counted last.