For those trying to sort out why prospects for Democrats look relatively poor for November, Gallup has supplied a very interesting data point in a study of interest levels in the elections. Here’s the most important passage:

The gap between young adults (aged 18 to 29) and older adults (aged 30+) in their election attention levels was relatively narrow in 2008 — 12 percentage points — but the 23-point difference today (42% vs. 19%) is similar to the average 26-point gap seen in October-November of prior midterms, from 1994 through 2006.

In other words, the “enthusiasm gap” is partially accounted for by the reemergence of a normal midterm election “gap” between the political involvement levels of younger and older voters, at a time when the former represent an unusually important bloc of pro-Democratic voters. But it’s worth noting that this gap is indeed normal for midterms; i.e., it cannot necessarily be associated with anything that’s happened since November of 2008. And as such, it is equally likely to shrink considerably during the next presidential election cycle.