LONELIEST POLITICIANS ARE PRO-CHOICE DEMOCRATS

WASHINGTON -- There is no one more lonely in American politics today than a Democratic elected official who opposes abortion.

Just ask Robert Casey. He is the two-term governor of Pennsylvania, a successful chief executive of a big state that is important in presidential elections, who in another era might have aspired to national office. But that path is closed to Casey in the age of the great abortion divide, because by all that is held holy in Democratic politics, Casey is a heretic. He is anti-abortion, and, worse yet, he won't shut up about it.

When the Supreme Court takes up the abortion issue again this week, it will focus on the 1989 Pennsylvania law Casey signed, placing limits on access to abortion. Casey will be in Washington to watch and to warn that the Democratic Party is gravely misreading the American will on this deeply troubling issue.

Casey is the most outspoken voice of the largely silent minority of his party: the pro-life Democrats. Like the pro-choice Republicans who chafe under the anti-abortion stance of their president and party platform, the anti-abortion Democrats are frustrated, uncomfortable and mostly mum on the subject. But not Casey.

It is no coincidence, he argues, that the Democrats have lost five of the past six presidential elections during a time when it became identified as the party of abortion.

For the past 25 years, ''too many Democrats in this country have had a bad feeling in their hearts and souls about the national Democratic Party,'' Casey said earlier this month in a speech on abortion, ''because the Democratic Party broke its historic compact with mainstream America when it volunteered itself asthe party of abortion on demand.''

In the past two decades, ''the party's position on abortion went from open toclosed,'' Casey complained. And ''millions of Democrats ... walked right out'' of the party, he said, because they disagreed with its unqualified embrace of abortion.

As a dissenter, Casey is hardly alone. Though they tend to keep quiet about it, nearly a third of the Democratic members of the House remain anti- abortion, including Democratic Majority Whip David Bonior of Mt. Clemens andhis Michigan colleague Dale Kildee of Flint. Up to 80 of the 268 House Democratshave voted against the pro-choice position on various abortion bills.

''This places us in an awkward position because top party leaders tout abortion rights as fundamental to the definition of the Democratic Party,'' observes Rep. Tim Penny, an anti-abortion Democrat from Minnesota. ''For us, as elected officials, it's frustrating and a constant struggle. But for rank- and-file Democrats'' who oppose abortion ''it is easy for them to just say 'the heck with the Democratic Party,' '' Penny adds. The opposing armies in the abortion battle paint the issue in black and white, but most Americans see shades of gray. Opinion surveys show that the public, much more ambiguous than the absolutists on both sides, seeks a middle ground.

According to a nationwide Gallup Poll last December, only 30 percent of Americans want the Supreme Court to overrule its 1973 decision in Roe v. Wade that secured a constitutional right to abortion; 64 percent oppose an overturn. But that doesn't mean most Americans oppose all state restrictions on abortion. A January Gallup poll that asked about the specific restrictions in the Pennsylvania law found this:

- 86 percent support requiring doctors to inform patients about alternatives to abortion before performing one.

- 73 percent endorse a 24-hour waiting period before an abortion could be performed, and a requirement that a married woman must notify her husband beforehaving an abortion.

- 70 percent approve requiring women under age 18 to get parental consent forany abortion.

- Despite majority support, such restrictions on abortion are anathema to pro-choice forces and national Democratic Party leaders. ''The national party has embraced the most extreme position - abortion on demand'' and has ''shut offall discussion'' of opposing views, contends Gov. Casey. It is seriously misreading the American mood on abortion, he argues.

Minnesota's Rep. Penny agrees. ''I think it's going to take only a few elections before the pro-choice crowd figures out that their extreme definition of abortion rights is not what America endorses,'' he says. ''That is going to be a painful lesson for the Democratic Party to learn.''

Casey argues that the Democrats should be open to debate on abortion and willing to reflect the anti-abortion views of many Democrats in its party platform. His argument is the mirror image of that of the pro-choice Republicans, who want the GOP to become a ''big tent'' that has room for differing views on this divisive issue.

''Our party used to be the 'big tent' party,'' comments Penny. ''We haven't learned the lessons of the past. We were a more successful party when a broad spectrum of people felt comfortable identifying themselves as Democrats.''

GANNETT NEWS SERVICE