In the U.S. presidential election campaign, Democrat Hillary Clinton was on the defensive Tuesday about a 1996 visit to Bosnia while Republican John McCain sought to boost his economic credentials. VOA National correspondent Jim Malone is following the campaign from Washington.

Senator Clinton is campaigning in Pennsylvania, which will host a presidential primary on April 22.

Public opinion polls give Clinton a comfortable lead in Pennsylvania over rival Barack Obama.

But for the second straight day, Clinton found herself playing defense over a visit to Bosnia in 1996 as First Lady.

Last week, Clinton said she recalled landing at the airport under sniper fire and that she and other members of her party had to run to vehicles with their heads down.

But news footage of the visit showed an apparently relaxed Clinton greeted on the tarmac by a welcoming group that included an eight-year-old girl.

On Tuesday, Clinton told a news conference that the long grind of the presidential campaign had caused her to misspeak about the circumstances of the visit.

"I made a mistake and, you know, I had a different memory," she said. "And you know, my staff and others have, you know, all kind of come together trying to sort out. So I made a mistake. That happens. It proves I am human, which you know, for some people, is a revelation."

Senator Obama will resume his campaign with a visit to North Carolina on Wednesday after a short vacation in the Virgin Islands.

Meanwhile, the presumed Republican candidate, Senator John McCain, focused on the economy Tuesday in a speech in California.

McCain said he is open to a variety of possible solutions to the home finance crisis in the U.S., adding that he would not allow what he called political dogma to override common sense.

"Let us start with some straight talk," he said. "I will not play election year politics with the housing crisis. I will evaluate everything in terms of whether it might be harmful or helpful to our effort to deal with the crisis we face now."

McCain has been criticized for focusing his campaign too much on the war in Iraq and not enough on addressing domestic economic concerns, which has become the top issue for voters.