Ohio has been much on the Fix mind of late as it becomes increasingly clear that it is the single state that Mitt Romney must find a way to win if he wants a credible path to 270 electoral vote and the presidency.

While everyone seems to agree about the centrality of Ohio to Romney's chances, we though we would bring a bit of cold, hard math to bear on the conversation -- arithmetic that proves beyond a shadow of a doubt why Ohio is an absolute must-have for the Republican nominee.

First, let's take a look at our current electoral map:

For the sake of argument, let's take Ohio out of Obama's total for the moment -- although we still believe it is leaning ever-so-slightly toward him.

That leaves Obama with 237 electoral votes to 206 for Romney. (Romney's total includes North Carolina, which we continue to believe he will win.) And, it leaves us with eight toss up states with 95 combined electoral votes. They are (from east to west): New Hampshire, Virginia, Florida, Ohio, Wisconsin, Iowa, Colorado and Nevada.

Give Romney Florida and Virginia. (And, yes, we realize both states are very close and could go either way -- but without winning those two the math becomes very tough for Romney.) He's at 248 electoral votes. Add Ohio to that and he's at 266 electoral votes.  That's the equivalent of electoral college layup for the win; Romney would only need to win one of New Hampshire (4 electoral votes), Nevada (6), Colorado (9) or Iowa (6) in order to be elected president.

On the other hand, assume Romney wins Florida and Virginia but loses Ohio. Now he needs 22 electoral votes to get to 270 -- the equivalent, given the state of the swing states, of something between a three-point shot and a half court shot to win.

That's because Ohio, despite population losses over the past few decades, remains one of the few swing state electoral vote treasure troves left on the map. Romney could win New Hampshire, Nevada and Iowa and still not equal the electoral votes he would get by simply winning Ohio.

To be clear: Even without Ohio (but with Florida and Virginia) there are paths for Romney to get to 270 electoral votes. (The most plausible? Win Colorado, Wisconsin and either New Hampshire or Iowa.)  And, 30-foot shots do occasionally find their mark. (If there were any justice in the world, of course, Gordon Heyward's heave back in the 2010 NCAA title game against Duke would have gone in.)

But, you'd rather have a layup to win the game than a 30-footer. That's the difference between winning Ohio and not for Mitt Romney. And that's why Ohio is the most important state in the country.

Just in case you need (even) more evidence, check out the video we did explaining the paths for Obama and Romney to 270 electoral votes.