(CNN) -- For the first time since the start of the election, merchandise for John McCain's campaign rivals sales of Barack Obama gear at CafePress, an online store specializing in user-generated T-shirts.
One eBay seller is auctioning off a piece of toast that she says bears the image of Alaska Gov. Sarah Palin.
The store saw a huge spike in sales on the day McCain announced Alaska Gov. Sarah Palin as his vice presidential pick, and McCain sales have been on the rise ever since.
"It was basically like Black Friday in retail terms," said Amy Maniatis, vice president of marketing for CafePress.
Within hours of McCain's announcement, the store had 2,000 McCain-Palin products. Now, there are 323,000. Popular items include shirts with pit bulls wearing lipstick, designs made just for "hockey moms" and a wide selection of anti-Palin gear.
"The Palin phenomenon is just kind of indicative that she has added life to his campaign. Whether people like her or don't like her, they are expressing themselves about her," Maniatis said.
Over at eBay, it's a similar story.
Two days before McCain introduced Palin to the country, no eBay users had any Palin items listed. The next day, one item showed up on the auction site. On the day of the announcement, there were more than 100 items on the site, and in the week that followed, sales skyrocketed. See some of Palin gear up for grabs on eBay »
Last week, listings for Palin-related items increased by 354 percent. In the same period, listings for Democratic vice presidential candidate Sen. Joe Biden decreased by 11 percent.
So far, more than 4,220 Palin items have sold on eBay, averaging $5.61 a hit. Most listings on the site are for low-ticket items, such as buttons, stickers, T-shirts and pictures. The most expensive was an autographed photo that went for about $500.
An eBay search for "Sarah Palin" now brings up all sorts of items, in addition to the usual campaign gear. One seller is offering what he says is her former home; another is selling Andy Warhol-style pictures of her; another listing shows a piece of toast that supposedly bears her image.
Palin's name also has been attached to items not related to her at all, something that eBay's pop culture expert says sellers do to drive traffic to their listings.
A similar thing happened when the "Sex and the City" movie premiered earlier this year. Sellers started adding the film's name to listings for shoes and other types of clothing.
"They are utilizing what is popular in pop culture to list their items. It is a real pop culture moment," eBay's Karen Bard said.
"When things grab the public's interest, it translates to sales on eBay," she said, and in the case of Palin, "it was only natural to see an uptick in things on eBay."
While hits online don't necessarily mean votes on Election Day, Harvard Business School professor John Quelch said the buzz surrounding Palin could at least cause some voters to give McCain a second look.
Obama has a lot of younger, center-left supporters, and "younger people obviously are more likely to openly express their political affiliations in terms of gear," said Quelch, co-author of "Greater Good: How Good Marketing Makes for Better Democracy."
If those on the center-right -- who Quelch says are less inclined to proclaim their political preferences on shirts -- start expressing their political leanings in increasing numbers, "that is really a very good indicator of momentum and energy," he said.
No matter what the outcome of the presidential race, at least online, Palin has breathed new life into McCain's campaign.
"In terms of the T-shirt polls, the announcement of Sarah Palin has really put the McCain ticket back in the race and energized the Republican Party in terms of actually making them a viable fashion statement," Maniatis said. "In a fashion-merchandise speak, Palin was his best accessory."