Sarah Palin Rolls Out at Rolling Thunder Motorcycle Ride

Sarah Palin's participation in the annual Memorial Day parade in Washington, D.C., has fueled as much noise about a potential presidential candidacy as the thousands of motorcycle-riding veterans participating in the Rolling Thunder ride-along Sunday.

At the Pentagon parking lot where the mob of veterans and their families pre-position for the thunderous two-wheeler march down Constitution Ave, Palin, who was not expected to address the Memorial Day crowd, said she was thrilled to participate.

"I love that smell of the emissions," she said, donning sunglasses and a Harley Davidson skullcap-style, black helmet.

Despite her low-key role, her presence is notable for the short notice and speculative chatter it has generated. Her appearance is part of the "One Nation" tour she announced just days ago on her SarahPAC.com website.

"It's imperative that we connect with our founders, our patriots, our challenges and victories to clearly see our way forward. A good way to do this is to appreciate the significance of our nation's historic sites, patriotic events and diverse cultures, which we'll do in the coming weeks on our 'One Nation' tour," she wrote, leaving open for debate any guess on her plans.

In recent polling, Palin scores at or near the top of GOP 2012 presidential hopefuls -- all without stating her plans. The Rolling Thunder parade attracts about 500,000 participants each year, and is a great place to go trolling for votes if she were setting up a bid.

"I'm glad she's here and she can ride on the back of my bike if she wants," one young rider told Fox News.

"I think her coming out shows a great support for the veterans which we haven't seen so far, either," a female biker said. "I think this will make a big difference in the minds of the veterans because there's a lot of us, you know, and it's important that we never forget them."

Asked by a man in the crowd if she was running, Palin responded, "Don't know yet."

But not all veterans at Sunday's staging were thrilled by Palin's presence, less so because of the politician she is, but because the event is meant to honor service members missing and killed in action.

"If she's here to support us and our troops, past, present and the ones that's name's written on the wall, that's fine. This is not a political event other than to call attention to the accounting of our MIAs, KIAs that have not been brought home," said one veteran.

Distant from the sweaty mosh pit of military members and supporters, pundits and lawmakers offered varying degrees of uncertainty about whether the 2008 vice presidential candidate and former Alaska governor was attending the parade as a prelude to announcing a presidential bid.

"She certainly is a major factor," said Arizona Sen. John McCain, Palin's 2008 running mate. "Whether she'll even run or not, I don't know. ... I believe that she can be very competitive."

McCain said if Palin runs, she will have to endure the endless viciousness she's encountered since popping on the national scene in September 2008.

"I've never seen anyone as mercilessly and relentlessly attacked as I have seen Sarah Palin in the last couple of years. But she also inspires great passion, particularly among Republican faithful," he told "Fox News Sunday."