This is basically a re-hash of a thread in the Election Trends board.
Here's what I said:
The article the OP quotes claims that Romney won 18 to 20 year olds in a landslide. If it's true, shouldn't we see at least a hint of that in 2014? 2012's 18-20 year olds were 20-22 in 2014.
In other words, the supposed Romney voting millennials should make up the majority of the 18-24 vote in 2014. Yet, Democrats do just as well among them nationally as their slightly older counterparts.
We did see a hint of that in 2014. Voters 18-24 were slightly more Republican than those 25-29, despite the fact that they included 23 and 24 year olds. The 2014 23 and 24 year olds were significantly more liberal than 25-29s or, especially, 18-22s. That was the generation most susceptible to buying into the "hope and change" in '08. Notice that 21 year-olds in 2012 (23 in 2014) voted 75% for Obama, while he lost the 18-20 vote handily.
There's one big problem with that.
In 2012,
Obama got 60% of the vote with both 18-24 and 25-29 year olds. In other words, these two groups were stationary with respect to each other between the two years.
Its almost impossible for this to make any sense if you assume a bunch of Republicans are entering the 18-24 age group. You'd have to do something weird like claim that the 23-24 year olds in 2012 were as Republican as the new voters in 2014.
Alright, there is a 3-point shift with how these groups voted compared to each other. This is due to 2012's Gary Johnson voters returning to the Republicans in 2014 (18-24 year olds were twice as likely to vote Libertarian than 25-29 year olds). Democrats perform equally well with both groups in both years, winning 60% in each in 2012, and 54% each in 2014. Meanwhile some 18-24 Libertarians returned to the fold for the GOP in 2014, giving them a slight boost in the cohort compared to the 25-29 group.