(Agencies)
Updated: 2008-04-17 09:32

PHILADELPHIA -- Hillary Rodham Clinton and Barack Obama both declined Wednesday night to pledge a spot on their ticket this fall to the loser of their epic battle for the Democratic presidential nomination.

"I think very highly of Senator Clinton's record, but I think it is premature at this point to talk about who the vice presidential candidates will be because we're still trying to determine who the nominee will be," Obama said in the opening moments of a debate six days before the pivotal Pennsylvania primary.

Democratic presidential hopefuls, Sen. Hillary Rodham Clinton, D-N.Y., right, and Sen. Barack Obama, D-Ill., arrive for a Democratic presidential debate at the National Constitution Center, April 16, 2008, in Philadelphia. [Agencies]

"I'm going to do everything I possibly can to make sure that one of us takes the oath of office next January. I think that has to be the overriding goal," said Clinton.

After nearly a week of increasingly personal criticism, both candidates seemed eager to temper their rhetoric.

Asked whether Obama could defeat likely Republican nominee John McCain in November, Clinton at first sidestepped. Asked a second time, she replied, "Yes, yes, yes."

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Asked an identical question, Obama said, "Absolutely and I've said so before" — a not-so-subtle response to frequent claims by Clinton's aides that he could lead the Democrats to defeat in the fall.

Obama has struggled in recent days to overcome the controversy caused by his comments that residents of small towns become bitter because of economic adversity, and "cling to guns or religion or antipathy to people who aren't like them" as a result.

He said he was attempting to say that because voters feel ignored by government, "they end up being much more concerned about votes around things like guns where traditions have been passed on from generation to generation. And those are incredibly important to them."

"People don't cling to their traditions on hunting and guns" out of frustration with their government, Clinton said. She added that Obama had a fundamental misunderstanding on the role of religion and faith.

Obama expressed frustration that the campaign has seemed to dwell on issues that have been taken out of context

A few minutes later, it was Clinton's turn to explain a mistake when she was asked about her erroneous statement that she had braved sniper fire during a landing in Bosnia as first lady in 1996.

"I may be a lot of things but I am not dumb," she said, adding that she had written in her book that there had been no fire during the event. "I'm sorry I said it," she said, adding that she realized she had "said some things that weren't in keeping with what I knew to be the case."

Obama was asked at one point whether he believed Clinton has been fully truthful as a candidate. "I think that Senator Clinton has a strong record to run on. She wouldn't be here if she didn't."

Obama's comments about bitterness have dominated the campaign in recent days.

Clinton has called them elitist, and aides have said they hoped to use the controversy to stoke questions about Obama's ability to defeat McCain in the fall.

Both campaigns are running television ads in Pennsylvania that focus on the flap.

Pennsylvania's primary has 158 convention delegates at stake, the largest prize remaining before the primaries end on June 3.

Obama leads Clinton in the delegate chase, 1643-1504. Earlier in the day, he picked up the endorsements of three superdelegates from a pair of states with primaries on May 6 — Reps. Andre Carson of Indiana and Mel Watt and David Price of North Carolina.

ABC News sponsored and televised the debate, with Charles Gibson and George Stephanopoulos moderating.