Between now and the election, we’re going to hear quite a bit of the conventional wisdom about winning the presidency: Tack right/left to win the party primary, then charge to the middle to win the presidency. Secure the base, win moderates, then take the oath of office.

Or not.

Jonathan Chait has gotten his hands on a paper (not yet online) by Emory political scientists Alan Abramowitz and Steven Webster demonstrating that while voters may call themselves “independent,” not only is straight ticket voting growing, swing voters have “nearly vanished.” Critically, this reality coincides with an increasing fear and loathing of the other side. Voters see a growing gap between their beliefs and the other party’s. This chart shows the gap:

Chait summarizes the practical result:

One common explanation is that it has become increasingly vogue, especially among college-educated voters, to describe yourself as independent, which implies that you form educated judgments about politics rather than blindly following the dictates of a party. Abramowitz and Webster add to this by introducing a phenomenon they call negative partisanship. That is to say, voters form strong loyalties based more on loathing for the opposing party than on the old kind of tribal loyalty (“My daddy was a Democrat, his daddy was a Democrat . . .”) that used to prevail. The party system has split along racial, cultural, and religious lines, creating a kind of tribal system where each party’s supports regard the other side with incomprehension and loathing.

I’m going to read the paper before commenting too much further, but if Chait’s summary is accurate — and that this new tribal system places an increasing premium on bloc voting (and, of course, getting your blocs to the polls) — then it raises a number of interesting political and questions, including:

1. Does the standard general election move to the center risk disillusioning more base voters than winning swing voters?

2. Does this mean the most “electable” candidate is now the one that can motivate the largest slice of the base?

3. If so, what color drapes will President Cruz hang in the Oval Office?

Chait seems confident that bloc voting favors Democrats, that the “coalition of the ascendant” is simply larger on the left. As for me, while I’m confident that bloc voting favors Barack Obama, I’m less certain that bloc voting will favor the next Democratic nominee.

Of course, this isn’t a new argument. Many conservatives have been arguing for years that selecting candidates on the basis of their ability to appeal to swing voters is a fool’s errand — and that a base-motivating strategy (like Senator Cruz’s) has a far greater chance of success. Abramowitz and Webster may have just given them some additional empirical ammunition.