If you listen to what the pundits are saying in the wake of the 2012 presidential election, Republicans might as well fold up their tents and go home. 

We can ignore, of course, those partisan Democrats who are urging Republicans to cease being Republicans and give the Democrats all the policies they want. But the relatively moderate and prudent election analyst Charlie Cook is saying “for Republicans, just doing the math is frightening” and the quirky conservative Patrick J. Buchanan suggests that Obama is following in the footsteps of Franklin Roosevelt and Richard Nixon in building a “new governing coalition” that will come to dominate American politics.
Reading this sort of analysis, one might be tempted to think that Barack Obama won the election by a margin of 23 percent (as Nixon did in 1972) or perhaps by 22.6 percent (as Johnson did in 1964). But in fact, Obama won with a margin of 3.8 percent.
But the argument is typically made on the basis of demographics. Prophets of Republican doom point to Obama’s large margins among young voters and minority voters, and assert that those voters will come to dominate American electoral politics.
It’s not quite so simple.  Youth have gone overwhelmingly for Obama. So if we assume what social scientists call “cohort effects” – that the Obama voters of 2008 will be Democratic voters in 2020 and 2040 – this might follow. But there are also likely to be “life cycle effects” – as people get older, they get jobs, make (in some cases) a high income, have children and buy property. Sometimes their political views change.
Note however, that even if the Obama cohort continues to be strongly Democratic, there is no reason to think that the younger cohorts following will be equally Democratic. Young people are particularly vulnerable to the zeitgeist – teenagers, for example, think that “everybody is doing it” is a sound moral argument. 
But the zeitgeist changes.  Young people have been rigorously indoctrinated about America’s unfortunate racial past. They have not been educated about the problems that afflict the black community today – single parent households, crime and drug use – since those topics are politically incorrect. The upshot is that they have been given the idea that the legacy of slavery, segregation and Jim Crow can be erased by electing a black man president.
It’s unlikely any black will be running for president on the Democratic side in 2016, and if one is, it’s impossible by definition for that person to be the “first black president.”
There was, in fact, a cohort of young people who leaned distinctively Republican in the early 1980s, apparently responding to the success of Ronald Reagan. As time passed, this Republican cohort moved back toward the average partisanship (leaning slightly Democratic), and succeeding cohorts also were quite average.  This is likely to happen again.
Blacks have given Democrats the majority of their votes since the New Deal, and since 1964 that majority has been extremely lopsided:  generally about 90 percent to ten percent.  What was unusual in the Obama elections was the very high level of black turnout – clearly the result of being able to vote for a black man.  While there is no reason to believe that a Republican will get more than ten percent of the black vote any time in the next few decades, it’s likely that black turnout will regress back to the normal pattern, becoming lower than white turnout.  Again, we have a Democratic advantage peculiar to the Obama elections, and no reason to believe that Democrats can recapture all of that advantage in 2016 and beyond.
Hispanics are especially important since they constitute the fastest growing segment of the population, and indeed 71 percent of them voted for Obama in 2012.  Yet in 2004, only 53 percent voted for Kerry.  Obviously, the immigration issue is tremendously important here, but Hispanics aren’t irrevocably attached to the Democratic Party. Immigration was highly salient in the years leading up to the 2012 election. If it is less salient in the future, or if the Republicans can craft a position that is both reasonably humane and also respects the rule of law (something the Democrats seem not to care about in this case), the Hispanic majority for the Democrats can be far less lopsided. Republicans should listen to Marco Rubio on this issue.
Smart Politics
Thus, the Republicans face no insurmountable barriers to winning the presidency in the future, or keeping control of the House or winning the Senate. It all depends on smart politics.  Republicans engaged in some stupid politics in 2012, nominating candidates who made bone-headed comments about rape in Missouri and Indiana senate races, for example. But Democrats have engaged in stupid politics too. The 2011-2012 recalls against Scott Walker and Republican Wisconsin legislators come immediately to mind.
The success of Republicans in winning state legislatures and governorships, not only here in “purple” Wisconsin but in blue states like Michigan and Pennsylvania shows that the party is capable of smart politics.   That smart politics wins elections is hardly a novel observation. The point is:  nothing in the demographics overrides this bit of hackneyed political wisdom.
Professor McAdams is an associate professor of political science at Marquette University. He writes at his Marquette Warrior Blog.