Most of the mainstream polls have had Obama in the lead for the last several weeks. However, one significant poll is one in which Romney leads -- the enthusiasm measurement.
The Battleground Tracking poll shows that Romney has a 13-point lead among voters who are "extremely likely" to vote. What's more, Romney's leads are significant among elderly and white voters, who have traditionally been high turnout groups. Meanwhile, Obama leads among young voters, blacks and latinos, who -- except for 2008 -- are not traditionally energized to vote, and their enthusiasm is down significantly from their 2008 highs.
So, although polls which ask random Americans or even registered voters may show Obama with a big lead, those likely to vote favor Romney. However, as I've said before, the only poll that really matters is the one on November 6.