Does Obama Have a Demographic Advantage?

First Read: “One of the more powerful undercurrents of this election has been the demographic advantage for the Democrats that every poll has found, with the degree of the advantage dependent on enthusiasm levels. The bottom line: Demography is an advantage for President Obama — and a challenge for Mitt Romney.”

“Our pollsters did an in-depth look at these fundamental shifts using all of the data we’ve collected over the last four month for the national NBC/WSJ poll. Our pollsters merged the numbers among likely voters from our two post-convention surveys from September, as well as our pre-convention June, July, and August polls and treated them as separate MEGA-surveys to compare with the 2008 exit poll. The results: Obama has seen erosion among men, whites (especially white independents), Midwest voters, and independents from what we saw in the 2008 exit poll. But that erosion has been offset somewhat by gains among Latinos (winning them 66%-32% in ’08 vs. 67%-25% June-Aug. and 71%-22% in Sept.), Democrats (from 89%-10% in ’08 to 92%-5% June-Aug. and 93%-5% in Sept.), and union households (from 59%-39% in ’08 to 59%-36% in June-Aug. and 61%-34% in Sept.).”