Enough about the 2012 election already. Let's talk 2016, which promises to be far more interesting -- and consequential.

The precise contours of that election, of course, will be shaped by what happens this November. Yet either way, the 2016 campaign will be, much more than 2012, a battle for the ideological soul of one or both parties.

That fight will be most intense if President Obama wins a second term. In that case, 2016 could be 2008 revisited, another wide-open race on both sides. And both parties will confront questions of fundamental identity: ideological purity versus political pragmatism.

The cascade of recriminations that would ensue after a loss by the likely Republican nominee, Mitt Romney, is already evident. Rick Santorum has been making the case that the party loses when it runs moderate nominees, pointing to Gerald Ford, George H.W. Bush, Bob Dole and John McCain.

"Every time we've run as a conservative, we've won," Santorum said earlier this month. "Why? Because Americans want a choice."

A Romney loss would pour kerosene on the conservative argument that voters want, as Barry Goldwater put it in 1964, "a choice, not an echo" -- that they prefer, in the later formulation of Ronald Reagan, "bold colors" over "pale pastels."

But the key question for Republicans is whether the correct lesson to derive from a Romney defeat would be that of Goldwater (landslide loss) or Reagan (two-term presidency).

I would argue, if Romney were to lose, that the message is not the candidate's deficit of conservative bona fides. Rather, Romney's problem is his dual lack of both political skills (grits, y'all?) and ideological convictions. He oozes inauthenticity, which threatens to repel conservatives and independents alike.

The 2016 argument for a return to conservative purity is especially unconvincing in light of the implacable demographic math of a future, more diverse electorate. Republicans will find it increasingly difficult to assemble a winning coalition if they cling to an unforgiving policy on immigration. Many on the Republican bench -- former Florida Gov. Jeb Bush, New Jersey Gov. Chris Christie, Florida Sen. Marco Rubio -- seem to get this. It's less clear that the Republican base does.

If Republicans face a potential debate in 2016 about the direction of their party, depending on the 2012 outcome, Democrats confront a near-certain one. This is a debate that was largely ducked in 2008. Earlier in that primary season, party divisions were mostly obscured in the shared revulsion to eight years of George W. Bush. Later, as the field was winnowed to Hillary Clinton and Obama, the divisions were more about competence than ideology.

Bill Clinton left office after two terms not only with an obvious heir apparent in Al Gore but having established a new model of a more centrist Democratic Party. If Obama wins re-election, he could have an obvious successor in Vice President Biden, who notably told CNN's Candy Crowley last October that "I'll make up my mind on that later."

But even if Biden chose to run -- at 73, he would be the oldest person ever elected president -- he would surely face significant competition for the nomination, if not from Hillary Clinton, then from the next generation of Democrats, among others New York Gov. Andrew Cuomo, Maryland Gov. Martin O'Malley and Virginia Sen. Mark Warner.

All of which suggests that the next election, not this increasingly stale, unenlightening campaign, is the one truly worth watching.