NBC Chicago – Barack Obama may have already won the presidential election.  An NBC/WSJ/Marist poll out Thursday found that nearly 1 in 5 respondents have already cast ballots in Ohio, which began early voting last week. Obama is winning those early voters by a 63%-37% margin; among those who plan to vote on Election Day, Obama is leading, 48%-46%.

Ohio is the most important state in presidential politics. It has voted for the winner in every election since 1964. It’s especially important for Mitt Romney. No Republican has ever won the presidency without winning Ohio. And considering that Obama has already locked up the electoral votes of California, New York and Illinois, and is leading in Pennsylvania and Michigan, Romney can’t get to 270 electoral votes without at least one industrial state. As The New York Times put it, “There are few credible paths to the White House for Mitt Romney without winning Ohio.”

That’s why, between now and Saturday, Romney and his running mate Paul Ryan will make four campaign stops in Ohio.

If the poll is accurate, Romney is already in a deep hole in Ohio. If he does as well in the next two debates as he did last Thursday, he could win the state; but Obama has votes in the bank, so it’s much easier for him to protect his cushion than it is for Romney to overcome it. If Obama wins the next two debates, or even draws, Romney has no chance in Ohio.

While Romney is now ahead in some polls of Virginia and Florida, Obama’s margin in Ohio has not budged. It’s still six points, according to the NBC/WSJ/Marist poll. General Motors, Ford, Chrysler and Honda all build cars in Ohio, so Obama’s bailout of the auto industry, early in his presidency, built up a lot of good will in the state.

Click here to read more.