LEWISTON — Despite mud, mist and knee-grinding hills, the inaugural Dempsey Challenge ended Sunday with smiles and sun.

“I’m just thankful it didn’t rain,” said Patrick Dempsey, the actor and Maine native who started it all. The gloomy sky broke minutes before he took the main stage for the closing ceremonies.

“It’s been a magical day,” he said.

It began beneath dark clouds, as more than 4,000 people packed the corner of Oxford and Beech streets. A white gate marked the start as Dempsey and a dozen or so donors, friends and world-class cyclists took off around 8:15 a.m for a 50-mile-long ride.

Mary Dempsey gasped and cheered as she watched the first cyclists pedal away, followed by the 100-mile group.

“Right from the start, it’s been great,” said Mary Dempsey, the actor’s sister and the coordinator of the Patrick Dempsey Center for Cancer Hope & Healing. “This is so heartwarming and amazing and touching.”

She continued to cheer as the 25- and 10-milers began their rides. Then she joined a 5k run/walk.

In all, 3,500 people registered to ride, run or walk. About 1,900 either ran or walked. More than 700 diehards entered the 100-mile ride, pedaling across much of Lewiston and Auburn and neighboring towns. The remaining 800 or so rode bicycles along shorter routes.

Between the registered entrants and a long list of sponsors, more than $1 million was raised, said Peter Chalke, president and CEO of Central Maine Healthcare.

About half of the money will be used to pay the event’s expenses. The other half will be used on the day-to-day operations of the Dempsey Center, said Chuck Gill, the hospital’s vice president for public affairs.

The center helps people who have cancer and their families, offering them education, massage, yoga and counseling. It’s based at Central Maine Medical Center. And it’s all free.

“The money raised will help keep it free,”  Gill said.

However, the Dempsey Challenge was meant to be about more than money. Some of the people who rode, ran or walked did so because they had survived cancer. Others recognized someone who had died. Some wore “in memorium” signs. Some decorated their jerseys or T-shirts. Some merely contemplated their lost family and friends as they rode.

Ann White of Auburn rode because she lost a brother and a mother-in-law to cancer. Her daughter and her husband are both survivors. She finished her route in about two hours and then found a spot about 200 feet from the finish to cheer the bicyclists as they arrived.

“Nice job,” she told some. “You’re done” she told others. “It’s just so nice to get that encouragement right at the end.”

Sue Bizier of Turner walked to remember her mom, Judy Marston. She and her friends wore pink T-shirts with the label,” Team Princess.” She and her teammates also managed to meet the charity’s namesake.

The star of TV’s “Grey’s Anatomy” spent part of Sunday afternoon followed by groups of 100 or more people, many snapping photos and squealing his name. He signed a lot of autographs and posed for photos.

Trisha Marston of Mechanic Falls, a teammate of Bizier’s, managed to snag Dempsey for a kiss and a signature on her T-shirt. She gushed as he walked away.

“He’s just so exciting and laid back, cool and giving,” she said, before admitting that she’s only a casual fan of his show. “I’m going to start watching more faithfully now.”

For Lewiston native Ron Lussier, the day was less about the star and more about his cause and his challenge. Cancer took Lussier’s father 10 years ago. It led him to ride farther than ever on a bicycle: 50 miles.

He and his teammates, Phil Burr of Boston and David Mallon of South Portland, each rode bikes that were at least 10 years old and had only a single working gear.

When they were finished, they all seemed relieved to have made it, particularly over the last hills and the last miles.

“It was tougher than we thought it was going to be,” Lussier said, calling the final hill “satanic.” He also seemed suspect of the mile markers, saying that they seemed to stretch at the end. “The last five miles felt like 10.”

All agreed it was worth the struggle.

Chalke, the hospital CEO, drew almost as much applause as Dempsey when he vowed in the closing ceremony that the event will continue.

“We will have another one next year,” Chalke said. “It will be bigger. Better.”

dhartill@sunjournal.com

People make their way down Adams Ave. during the Dempsey Challenge 5K run/walk in Lewiston on Sunday.

Breast cancer survivor Dolores Withee of Waterville reaches out to hug Patrick Dempsey before he begins his 50-mile ride during the Dempsey Challenge in Lewiston on Sunday.

Patrick Dempsey gives a thumbs up as he rides to the finish of the Dempsey Challenge in Lewiston on Sunday. Tour de France veteran George Hincapie, left, and professional racer Ted King, right, ride with Dempsey.

Click here check out more photos from the Dempsey Challenge.

Patrick Dempsey signs autographs for fans before he begins his 50-mile ride during the Dempsey Challenge in Lewiston on Sunday.

Matt Hird, 9, of Lewiston cheers for his brother Tom and cousin Emma Crovo at the beginning of the Dempsey Challenge 10-mile bike ride in Lewiston on Sunday.

Patrick Dempsey, second from right, turns onto Riverside Drive in Auburn at the start of Sunday’s Dempsey Challenge ahead of the main group of riders that were participating in the 50 mile ride.

Some of the riders cross into Auburn from Lewiston Sunday morning for the 50 mile ride in The Dempsey Challenge

Some of the riders cross into Auburn from Lewiston Sunday morning for the 50 mile ride in The Dempsey Challenge

Professional cyclists David Zabriskie, left, and George Hincapie talk prior to the start of the Dempsey Challenge in Lewiston on Sunday. Hincapie is a 14-time competitor of the Tour de France and Zabriskie rode the fastest Tour de France time trial in history.

A sea of bike helmets fill the horizon in the staging area of Dempsey Challenge 100-mile bike ride in Lewiston on Sunday.

Event organizers make room for Patrick Dempsey, center, to get through the crowd prior to the start of the Dempsey Challenge in Lewiston on Sunday.

People begin the Dempsey Challenge 5K run/walk in Lewiston on Sunday.