Out on the campaign trail raising re-election cash and promoting reading, Laura Bush (search) is staunchly defending her husband's credibility and taking a shot at Democrats who claim he skipped out on his National Guard (search) duty.

"I think it's a political, you know, witch hunt, actually, on the part of Democrats," the first lady said in an interview with The Associated Press.

The president served in the Texas Air National Guard during the Vietnam War and did report for duty in Alabama where he was briefly assigned, Mrs. Bush said.

"He knows that he served honorably," she said. "He knows that he showed up the whole time."

Mrs. Bush spoke Tuesday as she flew west on a three-day trip to Arkansas, California and Nevada to attend four fund-raisers and four education events. It ends Thursday in Las Vegas.

The first lady's demeanor is quiet and matter-of-fact, yet she sometimes must serve as the president's flak jacket when she's on the road, especially now as his approval ratings are drooping amid a recent barrage of Democratic attacks lobbed during the presidential primaries.

However, she seems to relish the role, traveling the nation to talk about education, especially reading among young students, and to bolster her husband's political positions.

"You know, I'm the one who has seen him up close and can tell people what he's like," she said, sitting on a couch in a private section of the plane and sipping occasionally from a bottle of water. "I've seen how steady he is, how he's steadied our country and how he's steeled our country for the fight against terror. ... I'm really proud of him. I love to have the opportunity to go around the country and talk about him."

Still, she admits being hurt by mostly Democratic allegations that he lied to the American people about his Guard duty, overestimated the potency of Saddam Hussein's weapons when U.S.-led troops went to war in Iraq and isn't taking the right steps to reduce unemployment.

"Nobody likes that part of campaigning — the personal attacks," Mrs. Bush said. "I certainly don't like it."

On other issues, Mrs. Bush said Americans need time to sort out their feelings about gay marriage, which she said was a "shocking" concept to many people. And she said abstinence should always be included in sex education.

Asked whether the president's brother, Florida Gov. Jeb Bush, will run for president, she replied, "I doubt it, but I have no idea."

Mrs. Bush said she and the president have been feeling a bit "nostalgic" as they watch the Democratic candidates campaigning in the snows of New Hampshire and Iowa.

"That's a much more up-close and personal campaign because you get to actually be with so many of the voters," she said. "We both miss that."

And she said that despite the lack of privacy that comes with being first lady - a title she finds "too artificial" - she doesn't feel as if she must constantly bite her tongue.

"I'm actually very disciplined," she said. "I don't really have to watch everything I say because I'm pretty well-behaved."

In a wide-ranging interview, Mrs. Bush put her stamp of approval on sexual abstinence programs, which would have their doubled under the president's latest budget proposal. Abstinence should be extensively discussed alongside contraception, she said. "I do think abstinence works. We know it works," she said. "It's 100 percent fail-safe."

Mrs. Bush wouldn't disclose her opinion on the issue of gay marriage, a hot-button topic on both coasts.

In California, gay couples have been lining up to get marriage licenses in San Francisco. On the East Coast, the Massachusetts Supreme Judicial Court recently ruled that its state constitution permits gay marriages — a ruling the president called "deeply troubling."

Bush has said that if judges "insist on forcing their arbitrary will upon the people," he would be forced to protect the "sanctity of marriage" by seeking a constitutional amendment to prohibit same-sex marriages.

So far, he hasn't.

"It's an issue that people want to talk about and not want the Massachusetts Supreme Court or the mayor of San Francisco to make their choice for them," Mrs. Bush said. "I know that's what the president thinks. I think people ought to have that opportunity to debate it, to think about it, to see what the American people really want to do about the issue."

But when asked how she feels about same-sex marriages, Mrs. Bush replied: "Let's just leave it at that."