JOHNSTOWN, Pa. -- Taking his last question at a Greater Johnstown High School "town meeting" Saturday, Barack Obama encountered an issue he neither expected nor welcomed: abortion. The eloquent senator from Illinois, who normally extends his answers with multiple digressions, made short work of a passionate pro-life woman asking about a "moral crisis" caused by abortion. After quickly explaining why "I am pro choice," he adjourned the event.

That brief encounter marked a rare departure from script last week as I followed the two contestants for the Democratic presidential nomination campaigning for two late primaries where each respectively is behind by double-digit margins in the polls -- Obama in Pennsylvania April 22, Hillary Clinton in North Carolina May 6. They each stuck to conventional liberal boilerplate, their language so similar that these two fierce adversaries could be called the Democratic twins.

Each backed away from the bitter conflicts that have marked their struggle. Neither mentioned serious problems that could yet cause grave damage for both candidates: racism by Obama's spiritual adviser and Clinton's made-up story of sniper fire in Bosnia. The tame questions by invited guests at what each candidate claims to be town meetings avoided the controversial or even the interesting.

But somehow the anti-abortion woman got into the high school gym here, and Obama by chance recognized her for the last question he would take. While he likes to stretch out his answers to embrace as many talking points as possible, he went into warp speed on abortion with the conventional pro-choice politician's mantra. "Nobody is pro-abortion," he said, contending that abortion should be a woman's choice after due consultation (though he improbably listed "her priest" as one of her consultants).

Abortion is the last thing Obama wants to be talking about in Pennsylvania, where many Democrats are pro-life. He would love to score an upset win in the state that would clinch the nomination, but the odds are long. With Gov. Ed Rendell's political organization backing Clinton, Obama was starting from scratch Friday when he launched a six-day Pennsylvania bus tour. Obama did get an unexpected endorsement that day from a major state figure: Sen. Bob Casey, who is Rendell's blood enemy. (The pro-life Casey was at Obama's side Saturday when he made his pro-choice declaration.)

Johnstown typifies problems Obama faces in Pennsylvania. Rep. John Murtha, whose steady flow of federal pork into the city has made him a Johnstown hero, strongly supports Clinton. So do most of the other local Democratic worthies, who showed up at the opening of Clinton headquarters a few hours before the Obama event. The black population of Johnstown is around 3 percent, though probably one in six at the town meeting was African-American. The only local speaker was Victoria King, a black volunteer.

The blacks at Obama's Johnstown gathering actually exceeded in number those who attended Clinton's events last week in North Carolina, where half the state's 2.5 million registered Democrats are African-American. For Clinton's first visit to the state as a presidential candidate, her endorsers appearing at events around the state were at the county commissioner level.

In backing away from attacks on Obama, Clinton did not even recognize her opponent's existence (though her aides were administering the usual battering of Obama in a media conference call while she was taking the high road Thursday in a town meeting at Fayetteville, N.C.). Talking to reporters after the Johnstown event, Obama said it was advisable for both candidates "to show some restraint" and added that he was "not blameless." However, while answering a voter's question Saturday, Obama could not resist saying that "the Clintons pushed NAFTA (the North American Free Trade Agreement)," which both candidates have assailed.

That was hardly the red meat the supporters of each candidate desired when they entered stuffy high school gyms and sat for long hours waiting for their candidate. Instead, they endured wonkish declarations, nearly identical from Obama and Clinton, on corporate tax policy, college tuition, alternative energy sources and other items on the liberal laundry list. Obama thinks he has the nomination won, and Clinton is not desperate enough to launch a suicidal last attack.