As the president and his Republican challenger prepare for their second debate tonight, Commentary blogger Jonathan S. Tobin documents the stakes for Barack Obama.

As the Real Clear Politics Electoral College Map shows, the president’s seemingly overwhelming advantage in terms of states that are solid, likely or leaning in the Democrats direction is evaporating. It currently shows Obama with 201 Electoral College votes and Romney with 191 with a whopping 146 in states where the average margin in recent polls is less than five percent for either candidate. But with Romney steadily gaining ground even in states that few serious people thought would even be in play, like Michigan and Pennsylvania, the ebbing confidence among liberals is justified. The question now is what, if anything, the president can do to reverse this momentum shift that appears to be on the verge of sweeping him out of the White House.

The most obvious answer is for Obama to be seen to beat Romney in either or both of the remaining debates. But, as history shows, decisive wins or loses in these affairs such as the one Romney scored earlier this month are the exceptions. So long as both men show up prepared, look interested (something Obama failed to do on October 3) and don’t make any glaring mistakes, it isn’t likely that either side will reap that much of a benefit.

There is the chance that some “October surprise” will pop up abroad that will reinforce the president’s status as commander-in-chief. Should some of those who assassinated the U.S. ambassador to Libya be killed or captured before Election Day, it may be that this will reinforce the Democrats “bin Laden is dead” theme and give the president the boost he needs even if that also prompt some “wag the dog” cynicism about the action.

But the Libya debacle illustrates that incumbency brings perils as well as advantages. It is likely that the president will spend the next three weeks continuing to try to dodge questions about what he knew about the consulate’s requests for more security and the fact that there was no demonstration about a video prior to the killing and when he knew it. Libya also contradicts the claim aired in his re-election ads that America’s enemies have been beaten.

This should encourage Republicans, but if there is anything we should have learned in the past two months it is that this election is not so easily predicted, as the pundits would like. The unexpected shifts in the polls after the conventions and the first presidential debate illustrate the fact that the nation is still nearly evenly divided.