Candidates will have plenty to talk about

Looks like it's time to rumble, not ramble.

Tonight's Democratic presidential debate at the National Constitution Center comes at the most contentious point in the Pennsylvania primary campaign, with both candidates running TV ads attacking each other by name.

U.S. Sen. Barack Obama is struggling to recapture momentum after his widely criticized remarks about "bitter" Pennsylvanians, and U.S. Sen. Hillary Clinton is seizing on the gaffe to make a decisive move before time runs out on her efforts to capture the nomination.

"After this past week, this debate is a much bigger deal," said veteran media consultant Neil Oxman. "Everybody knows this race was getting close, and something happened to change the dynamic. This is Obama's chance to set this aside and get back to his 'change' conversation, or not."

Clinton and Obama have appeared together more than 20 times, but tonight will be their first debate in front of a live, prime-time, major-network audience.

ABC News, which is co-sponsoring the event with the Constitution Center, will broadcast the 90-minute debate beginning at 8 p.m.

"It's been two months since they've debated and there's plenty to talk about," said ABC's George Stephanopoulos, who will co-host with ABC anchor Charles Gibson.

Clinton and Obama last faced off Feb. 26 in Cleveland. Since then, the two have campaigned heavily in Pennsylvania, and Clinton's lead has shrunk from 12 points in a February Daily News/Franklin & Marshall poll to 6 points in a survey taken over the weekend.

Clinton is now running two TV ads attacking Obama: one on his comments about bitter Pennsylvanians clinging to guns and religion and distrusting those not like them; the other on his contributions from oil-company employees and his vote on a congressional energy bill.

Obama has responded with an ad that features a Pittsburgh audience booing Clinton when she begins attacking Obama.

Stephanopoulos, asked if he expects the candidates to go after each other tonight, said, "I can't game it for them. I can see risks and benefits either way . . . that's one of the things that makes this exciting. I don't know what their approaches will be."

Oxman said the recent controversy is bound to come up, and Clinton needs to make her point "without going crazy over it . . . She wants to appear knowledgeable and experienced, without being glib or smug."

Obama, Oxman said, "has a chance to say 'Hey, I'm not the elitist on this stage' and point to the Clinton's wealth . . . I don't think he's done a good job yet of condensing his answer down to a good 35 or 40 seconds."

For the Constitution Center, hosting the debate is a welcome reward for months of effort.

Center president Joe Torsella said he tried to get a debate at the center before the Feb. 5 Super Tuesday primaries, and again before the March 4 Texas and Ohio contests.

"By the time the Pennsylvania primary came around, the campaigns knew who we were, and the third time was a charm," he said.

Torsella said it helped that both campaigns got calls from the center's congressman, U.S. Rep. Bob Brady, who, Torsella noted, "is one of the great American uncommitted superdelegates." *