With less than 100 days to go before the election, President Obama has a decisive advantage in 12 swing states that would give him a comfortable margin of victory in the electoral college if the election were held today.

The Hill:

The crucial battleground states number about a dozen: Colorado, Florida, Iowa, Missouri, Nevada, New Hampshire, New Mexico, North Carolina, Ohio, Pennsylvania, Virginia and Wisconsin. 

Taking the polling averages used by Nate Silver in the New York Times, the president is ahead in 10 of the 12 vital states. If those polls were borne out on Election Day, Obama would coast to victory with 332 electoral college votes. Only 270 votes are needed to win the presidency.

Awarding Obama only the states in which he now leads by 3 percentage points or more in the polling averages still sees him safely home. 

By that measure, as of last Friday, he would win 8 of the 12 battlegrounds, for a total of 290 electoral votes.

Romney victories in Florida, Missouri, North Carolina and Virginia would leave the Republican marooned on 248 electoral votes.

Strategists including Karl Rove have, in recent months, noted that Romney's path to victory is a challenging one in terms of the electoral map. 

Now, Democrats are citing the same argument to justify their guarded confidence.

"All the swing states this time are places [Obama] has been able to win in the past," said David Beattie, a Florida-based Democratic pollster. "Some of them, like Nevada and Colorado, are pretty solidly in his direction. One of the most optimistic things for Obama is that Iowa and Virginia are still regarded as swing states."

It should be stressed that several of these states are going to be more competitive than they are now. And there's a chance that the upper midwest states of Michigan and Minnesota can be added to that list if Romney continues to poll well.

The math is daunting for Romney but far from impossible. A strong convention will go a long way toward closing the gap and making Obama sweat.