LEWISTON — Even the McDreamyBiker is having a tougher time.

Shannon Gilmartin, the Dempsey Challenge’s top individual fundraiser in 2009, has halved her fundraising goal. Too many people were saying no.

“I got so many (replies back), ‘I’m really sorry. I support the cause, but I can’t this year,’” said Gilmartin, who lives outside Buffalo, N.Y., and will bike the 100-mile event for the third time.

Captain of the (so far) top fundraising team, she uses the handle @McDreamyBiker to talk about the challenge on Twitter. “I think the economy has really hit my fundraising and I know my other teammates as well are seeing that,” Gilmartin said.

With a little more than a week to go before the two-day Dempsey Challenge on Oct. 8 and 9, event organizer Aimee Arsenault said some figures are down, but she’s optimistic for a last-stretch catch-up.

The event is the primary fundraiser for the Patrick Dempsey Center for Cancer Hope & Healing and headlined by Dempsey, who plays Dr. Derek “McDreamy” Shepherd on the ABC TV drama “Grey’s Anatomy.” The center helps thousands of cancer patients, their families and caregivers every year at no charge.

This year’s Dempsey Challenge goal: 5,000 runners, walkers and bikers. So far: 3,200, down 900 from last year.

Hundreds of volunteer spots — to cheer people up hills and help them cross roads — are left to be filled.

Arsenault said fundraising is on pace with 2010, which is good news, but there’s “a really long way to get to our goal.”

“My hope and dream is that they’re procrastinating,” she said. “We’ve been trending lower than this time last year pretty much all along. We’ve sort of been waiting for that big surge to happen.”

She said $550,000 had been raised so far toward the $1.4 million goal. The challenge raised $1.2 million last year, all of which goes to the center. Sponsors pick up the cost of holding the event.

Simard-Payne Memorial Park will serve as event headquarters. It will also serve as the starting point for Saturday’s 5K and 10K run/walks and Sunday’s five bike events with courses between 10 and 100 miles.

Dempsey will bike the 50-mile course with professional racers and Olympic hopefuls.

Participants in the challenge are asked to raise a minimum of $150 and to pay an entrance fee: $35 for a run/walk, $75 to cycle or $100 for both.

Registration is trending toward more runners/walkers than cyclists, similar to years’ past.

Arsenault said she had heard about people holding back because of the economy, and she had heard mixed feedback on the timing of Columbus Day weekend.

Participants can register up until the morning of their event, she said. “Hopefully, folks will be able to show up last-minute and really boost those numbers.”

Challenge volunteers can sign up in advance or on that weekend. Arsenault said 400 people have offered so far to fill about 600 of the 900 volunteer shifts.

“Our biggest need is ride marshals for the course on Sunday,” she said. “Those are the folks that stand at intersections and help people. Those are really important positions because the roads are not closed for these routes. Safety is a really big concern of ours.”

Gilmartin, a mother of three who started biking to get back in shape, said an ongoing raffle for a pair of scrubs signed by Dempsey has been one of her biggest fundraising successes. Her original goal was to raise $10,000. She’s now just over $5,000.

Vivian St. Onge, an oncology nurse at Central Maine Medical Center, which houses the Dempsey Center, credited her sister, Sue Donovan, with organizing a wine-tasting and decadent dessert event in August that pushed St. Onge into this year’s second-top individual fundraising spot with more than $7,000.

St. Onge was diagnosed with breast cancer last October. After months of treatment, she said she was not up to her cycling best but plans to tackle the 50-mile course. She has used the Dempsey Center during her recovery, a place she says is “like family.”

“I think that everyone, everyone today is touched by cancer somehow, so I just think it was easier to open up your hearts (to donate),” St. Onge said. “There was no hesitation. It was amazing.”

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