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.