The most common diagnosis is that Republicans are just too conservative for young voters. But I wouldn’t worry about, if I were a Republican …

3. The GOP issue isn’t the youth – it’s everyone

Mitt Romney did worse across pretty much all age cohorts compared to President Bush in 2004.

Bush only won 43% of the 18-24 year-old cohort. There wasn’t much of an outcry about Bush’s young voter problem because he won. Two elections later, Romney won about 40% of the now 26-32 year-olds. This 3pt drop was entirely consistent with a national Republican drop of 3.5pt from Bush’s 50.7% to Romney’s 47.2%.

Other age groups are consistent with that effect. Bush won 53% of the then 30-44 year-old vote. This time, Romney nabbed 50% of the now 40-49 year-old cohort, which again matches the Republican drop of 3pt nationally. Same with the then 40-49 year-old vote, where Bush grabbed 54% and Romney walked away with 52% of the now 50-64 year-old cohort.

None of this is too surprising. As I wrote last week, age cohorts tend to remain at the same level of partisanship relative to the mean. A cohort’s “liberalism” or “conservatism” is dependent on the success of the presidential administration they come of age under. The now 26-32 year-olds came of age during the not too successful Bush administration and pretty solid Clinton years.