While much of the polling has tightened up, President Obama still holds a significant lead in Ohio. According to Public Policy Polling, Obama is up by five in the critical swing state. From PPP:

PPP’s newest Ohio poll finds Barack Obama leading 51-46, a 5 point lead not too different from our last poll two weeks ago when he led 49-45.

The key finding on this poll may be how the early voters are breaking out. 19% of people say they’ve already cast their ballots and they report having voted for Obama by a 76-24 margin. Romney has a 51-45 advantage with those who haven’t voted yet, but the numbers make it clear that he already has a lot of ground to make up in the final three weeks before the election.

We’ve found a major improvement in Mitt Romney’s image in most of the states that we’ve polled since the Presidential debate, but Ohio is an exception. His favorability now is a 45/51 spread, showing no improvement from his 45/49 breakdown two weeks ago. Obama meanwhile has seen a small spike in his approval rating, from 48/49 to 50/48.

With Obama already banking a large lead among people who have already voted, it is going to be difficult for Romney to make up ground in Ohio.

There are technically paths for Romney to get to 270 without Ohio, but they are not easy. If Romney loses Ohio he will basically need to sweep the other swing states.

Ohio remains Obama’s firewall.