"Demographics is Destiny" is a popular mantra of the left when it comes to winning future elections. Their theory goes that the Democratic party dominates Black, Hispanic, and youth voters. Blacks and Hispanics are likely to become an increasingly large portion of the electorate and every year new voters turn 18, while older voters die. There are some holes in this theory and two articles suggest that this may not be so. Doug Sosnik, the political director in Bill Clinton’s White House, the political director in Bill Clinton’s White House expressed his thoughts">expressed his thoughts, while the Washington Post looks at a census report.
According to the census bureau the 18-24 segment voting went from 49% to 41%. There was a smaller drop in 25-44. We can probably assume that some of that drop was the younger 25-29 group. The assumption that the Washington Post is making is that non-voters in this group would vote like the people that actually vote, but if they don't show up, they won't help Democrats. Of course, we don't know how they will vote, but we may have an idea of how they voted in 2008.
Obama got 66% of the 18-29 vote in 2008. If 49% of these people in 2008, then a group of 200 18-29 voters, would've voted for Obama 66 to 32. In 2012, Obama got 60% of the 18-29 vote. If 41% of these people voted, Obama would've gotten these voters 49 to 30. If this is the case, Romney didn't actually do better with the 18-29 segment. What happened was that 17 Obama voters stayed home and 2 McCain voters.
So the 60%-37% vote in 2012 wasn't good news for Republicans. They may have lost voters. It's just that it's really bad news for Democrats. Many of those 17 Obama voters will show up as they get older. As will some other 2008/2012 non-voters. I have no idea who they'll vote for, but I'd guess Democrats will have to earn their vote. The assumption that they'll automatically get it seems foolish.