WASHINGTON — The Pennsylvania Turnpike was a highway to nowhere for Barack Obama.

For those looking at the contest for the Democratic presidential nomination with clear eyes, the turnpike resembles nothing so much as the ribbon of highways that connect the old industrial towns and the rural hinterlands of neighboring Ohio. Obama’s campaign rode them to a dead end in that other battleground state, too. No amount of bowling and beer-sipping for the cameras seems to help Obama with those voters who decide a candidate’s fate in the Rust Belt.

Despite the media’s focus on Hillary Clinton’s nine-point winning margin over Obama in the latest mega-state primary — not enough, as we all know, to overcome Obama’s lead in the delegate count toward the Democratic presidential nomination — the map of the Pennsylvania outcome shows what President Bush would recognize as “a thumpin’.” Obama won only seven of Pennsylvania’s 67 counties; in Ohio, he won five of 88.

He carried Philadelphia handily, as expected. But his presumed firewall in the suburbs cracked. Clinton beat him in two of the four suburban counties that ring Philadelphia, trouncing him in Bucks County, home to one of legendary builder William Levitt’s original communities for those who sought a modest house in which to fulfill their highest aspirations.

Much has been made of the powerful demographic divisions that have nagged the Democrats all the way back to the Iowa caucuses, where Obama won but where his weakness among less affluent and older voters first became obvious. The divide — a split in the Democratic coalition that dates to the 1960s — grows more stark. The white, working-class voters now seem entrenched in their support for Clinton. So, too, are African-Americans and affluent, educated whites mostly wedded to Obama.

In Pennsylvania and states like it — Ohio and Michigan come most easily to mind — this is not just a difficult hurdle for Obama to clear should he become the nominee. It is beginning to look insurmountable.

John Kerry barely took Pennsylvania in 2004, ending up with a margin over Bush of just 2.5 percentage points — down from a four-point victory that Al Gore had achieved in 2000. Even so, Kerry ran more strongly among the very demographic groups and in the very regions of Pennsylvania where Obama fared the worst on Tuesday. And that was in a general election, where vastly more voters cast ballots and those who do so are not necessarily strong partisans.

Kerry, for example, won among Catholics, with 51 percent of their vote, according to the 2004 network exit polls. Obama managed to capture only 30 percent of the Catholic vote in Tuesday’s primary. Kerry lost white women to Bush, 51 percent to 48 percent. Obama lost white women to Clinton on Tuesday, 68 percent to 32 percent.

It is the map, though, that shows the uncertain route Obama faces in a state like Pennsylvania in November.

In 2004, Kerry won Philadelphia and its suburbs. But he also ran strongly in northeastern Pennsylvania — the area that includes such cities as Scranton and Wilkes-Barre — beating Bush with 51 percent of the vote there. Clinton trounced Obama in this area, racking up a 32-point margin over the Illinois senator.

In the Pittsburgh area, where Kerry’s wife, Teresa Heinz Kerry, is a well-known philanthropic and political figure, the 2004 nominee beat Bush with 53 percent of the vote. In the Pittsburgh area on Tuesday, even with Heinz Kerry’s campaign help, Obama was crushed. Clinton bested him there by a margin of 62 percent to 38 percent.

The Democratic superdelegates who will decide the nomination — neither Obama nor Clinton can grasp it without them — must soon choose. The decision increasingly seems not so much to be one between Clinton and Obama. It is more fundamental.

Do they want to win back the White House? If they do, the persistent pattern of Obama’s failure to win swing voters in fall battleground states would clearly move them toward Clinton. Do they want to keep peace with the African-American voters who are Democrats’ most loyal supporters — but whose votes aren’t necessarily decisive in key states that will decide the November outcome? That calculus favors Obama.

Or do they just want to hold on to their own congressional seats, Senate sinecures and governor’s mansions? Crude self-interest is always the easiest call.

Marie Cocco’s e-mail address is mariecocco(at)washpost.com.

© 2008, Washington Post Writers Group

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