There is no ideological swing to liberals
The ideological composition of the American electorate hasn't changed dramatically. Self-identified liberals were 25% of voters in 2012 and 23% in 2008. Conservatives were 35% of voters in 2012 and 34% in 2008.
By some measures, voters are less liberal today than they were four years ago. In the 2008 exit poll, 51% said "government should do more to solve problems" while 43% felt "government is doing too many things better left to businesses and individuals." In 2012, 43% said "government should do more" and 51% believed "government is doing too many things." While 44% wanted ObamaCare "expanded or left as is," 49% wanted to "repeal some or all of it."
Another sign that Mr. Obama hasn't fundamentally changed America's political structure: Compared with 2008, there were 371,800 fewer white votes cast in Ohio in 2012, when Mr. Obama carried the state by 166,214 votes. Many whites who voted for him in 2008 couldn't bring themselves to do so again or to vote for Mr. Romney. Their staying home represented a tactical victory for Mr. Obama, not a strategic realignment.
Nor can Democrats count on young people forever remaining Democrats. Voters age 18-29 were those most likely to move away from Mr. Obama between 2008 and 2012, and Republican identification generally increases as people graduate college, start work and begin families. Of those who were 18-29 years old in the 1972 election, 47% were Democrats, 26% Republicans and 28% independents. By 2012, these same voters (now ages 58-69) were roughly 37% Democratic, 34% Republican and 29% independent. They backed Mr. Romney by 51%-47%.
Does anyone think every future Democratic candidate will enjoy the unusually high African-American turnout and victory margin of Mr. Obama?I have made the point about the young voters before. They get older and wiser once they start looking at what is taken out of their paycheck, and if they are running a small business they really wise up as to what Democrats are doing to them.