Now that the dust has settled, big labor’s big midsummer crack-up is beginning to look a lot different.

Last month’s conventional wisdom: The showdown in Chicago was labor’s experience with assisted suicide. My guess for next month’s conventional wisdom: This was labor’s adoption of the heal-thyself ethic, and none too soon.

No one is contesting the notion that organized labor is a smaller part of the broader culture than it was in generations past. A half-century ago, nearly a third of American workers were union members. Today it’s about an eighth. Cultural and economic changes like that are significant but not abnormal; only two decades ago, AT&T was considered a high-tech leader and was an indispensable part of the smart stock portfolio.

The labor movement always has prided itself on its progressivism but always has been slow to change. (Same with the academic world, and, now that you mention it, journalism, but that’s another story.) Now labor knows it must change – or die as a political force. That’s the essential insight that led to the split between the AFL-CIO, which this year is celebrating the 50th birthday of the federation, and the new Change to Win Coalition.

GOP hopes for gains

This split did not exactly displease Republican strategists, hopeful that the elimination of labor as a Democratic force – a force that voted for Sen. John F. Kerry of Massachusetts over President Bush in 2004 by a margin of 2-to-1 – would allow them to target the next great Democratic bulwark, black voters.

Their sense of triumph may be premature. If the labor movement truly can change, then maybe it can win – or at least help the Democrats win the White House or one house of the Congress sometime before the decade is out.

The laws of mathematics work in politics: As population grows, the percentage of union voters gets smaller. And while union membership itself shrinks, the impact of the union vote diminishes. Right now it’s about a quarter of the electorate.

But for years the Democrats have failed to understand that the eclipse of the labor movement nationwide doesn’t necessarily mean that the political importance of labor is in decline. Presidential elections, as the Democrats should have learned in 2000 and plainly didn’t by 2004, are not national. They’re run in key states, and in the states of Pennsylvania, Ohio and Michigan, about a third of the electorate has union ties – and about two-thirds of them vote Democratic.

Unions a boon to Democrats

Here’s the Democratic challenge: The party’s three most loyal voting groups are blacks, Jews and union members. There’s not much the Democrats can do to grow more blacks or Jews. But they can make more union voters, who voted Democratic in 2004 by a margin of 32 percentage points – a figure that, in the last two elections, rises to 37 percentage points in battleground states.

(How great is the union advantage among white voters? In the 2004 election, all white voters favored President Bush by 17 percentage points, five more points than they had in 2000. But white union members favored Kerry by 24 percentage points, a bigger margin than Vice President Gore had in 2000.)

Rather than wringing their hands, some labor analysts are arguing, the Democrats should figure out how to foster union membership.

So the crisis for Democrats may not be that there are two competing labor organizations and that a Democratic candidate is going to have to get two endorsements rather than one. The crisis may be that, until this summer, there was no real energy in the effort to recruit new union members. Now there is, or at least that’s the theory.

If the union split brings on a recruiting war, or if it permits the breakaway unions to go on a recruiting spurt, then the number of union voters, and thus the Democratic advantage, grows. (Take a look at how unionization among government employees has risen in the past quarter-century, from about 25 percent of the work force to 36 percent. No mystery why the Republicans want to shrink government.)

Not that newly energized union recruiting efforts will necessarily provide a newly energized Democratic Party. New survey data from the Pew Research Center suggest that Republicans are gaining real strength among Americans in the middle- and lower-middle-income brackets, groups that, as Pew says in a poll analysis released last week, “contain the people who are either union members or likely targets of membership drives.” These are swing voters in the workplace as in the polling place. So it’s not a sure bet, but it’s the best one the Democrats have right now.

Get-out-the-vote efforts

Now to the next specter raised by the union divorce: the so-called threat to the efficacy of get-out-the-vote efforts.

This may not be the peril that the whiners think it is. Some political pros consider the labor councils and state federations stodgy, rusty, old and ineffective. (There are exceptions, like Cleveland and Seattle.) Much of the energy in recent get-out-the-vote efforts (plus about $44 million in cash, which is real money) has come from national offensives, perhaps the only known example where it is true that officials from Washington arrive on the local scene to help things rather than to bollix them up.

The AFL-CIO has an exceptionally effective program to build mail and phone connections during election seasons. Building an equally effective system is one of the biggest challenges facing the new labor renegades. But labor may learn a lesson from capitalism: Competition is good. The Change to Win group is going to want to get credit for its effort. The AFL-CIO is going to want to get credit for its.

Plus this: The chances are that a Teamster who used to work with a firefighter to win Democratic votes isn’t going to lose his enthusiasm just because some bigwigs in Washington are fighting with each other. Chances are that even the bigwigs will be fighting on the same side in 2008.