Deciding quickly, for balance

WINNING the presidency, like running a White House, is something a candidate must do chiefly by himself. Still, the naming of Sen. Lloyd Bentsen of Texas as his running mate does do several things for Michael Dukakis. It gives him a Southern assist. Senator Bentsen gives the Democratic nominee a better chance of winning Texas, whose 29 electoral votes are crucial to a Democratic victory on Nov. 8 - but it by no means guarantees the Democrats can carry Texas against George Bush, also a Texas ``native son.'' Mr. Bentsen likewise helps Mr. Dukakis generally in the South, where the more moderate and senior Bentsen will help offset Dukakis's Northern liberal image. But Florida, also a key big state, already looks lost to the Democrats. And, in the South, Sen. Sam Nunn of Georgia might have helped more.

A Washington assist. As chairman of the Finance Committee, and in most matters a Washington heavyweight, Bentsen would bring the kind of Capitol Hill experience needed for a credible ticket. He would help balance off the potential presence of a Sen. Robert Dole on the Republican side. In some regards, a Dole is more crucial to the GOP ticket, where he would also help offset Bush vulnerabilities among Midwestern farmers and blue-collar workers. If issues like the federal deficit and taxation are primary concerns for the next president, Bentsen can make an intelligent contribution.

It settles the Jackson question. For weeks, the Dukakis presidential story has been bedeviled by the status of Jesse Jackson. The Rev. Mr. Jackson has done a masterly job of playing the ambiguities of this situation, to enhance his own status at the convention. Naming Bentsen early gives Dukakis a better chance of getting the convention to focus on a Dukakis ticket and its Democratic message for 1988. But only a better chance: Jackson still has a handful of potentially distracting cards to play, if he chooses to play them.

Now, what naming Bentsen doesn't do:

It doesn't help much in pivotal states like Ohio, which Sen. John Glenn would have helped secure, or California, which will likely settle the outcome in November.

It won't ensure that the Democrats will maintain their current Electoral College lead. This lead reflects, for Dukakis, publicity for a series of Tuesday primary victories against an even more liberal Jackson, while the Bush campaign had fallen out of the news for want of a challenger. If all goes well enough next week in Atlanta, the convention publicity should push the Democrats ahead a bit again, until the Republicans do their thing in mid-August in New Orleans.

In the end, voters will view the election chiefly as Dukakis matched against Bush.

The choice of a running mate may well be important for reasons of governance - picking a potential backup president, no less. But at this stage of the process, naming No. 2 chiefly reflects on the judgment of No. 1.

Northeasterner Dukakis has picked a seasoned, intelligent, moderately conservative running mate from the Sunbelt - someone who will also make sense to the investor class and help offset the Democrats' big-spender image.

In this case Dukakis went for balance. And he decided quickly and early.