WILLMAR – As the sky darkens, the Christmas lights in Chad Koosman's yard grow more brilliant.

All 400,000 of them.

The stars, reindeer and spinning, 40-foot trees bounce to a beat that onlookers tune their car radios to as they enter through a glowing tunnel. When the music picks up, the lights dance red to green. When it slows, a slender tree shimmers white. Angels appear in the distance.

"I'm kind of crazy when it comes to Christmas lights," said Koosman, 32, of the 45 miles of LED lights, 7 miles of extension cords and 15,000 zip ties required.

The display, called "Celebrate the Light of the World," now draws thousands. Their donations constitute half the local Salvation Army's seasonal take. The show has hosted several marriage proposals, including Koosman's own — to a woman he met after she stopped one night to see the lights.

But it all started with Koosman's simple resolve to be a better bell ringer.

Six years ago, Koosman started ringing for the Salvation Army and quickly began battling the top donation-getter in town. "I couldn't catch this guy," Koosman said. "I'd ring for four hours, he'd ring for six. If I'd do five, he'd do nine."

Koosman later asked to put a kettle at his house at 3903 60th Av. NE, where his display had reached 100,000 bulbs. A photo from that time shows lights lining his roof, a dozen trees and the words "Merry Christmas." It bears little resemblance to the blinking, bopping spectacle of today.

He raised about $800 the first year, a big help, said Randy Stahl, then the Willmar Salvation Army corps administrator. "That was money we didn't have to ring bells for." But to Koosman, it wasn't good enough, Stahl said.

"He decided he was going to do something different," Stahl said. "And it's exploded every year since."

On a recent Saturday, boosted by photos with Santa, visitors dropped $7,600 into the kettle. Some context: A strong, four-hour shift of bell ringing might bring in $250, said Stahl, who now works for the Salvation Army in Hibbing.

Last year, the Willmar display raised $70,000 — bringing the total to $250,000. Counting corporate matches, this year's show, which runs through Jan. 4, could hit $100,000.

"There are good families out there that are deserving and that need a helping hand," Chad said.

A love story

Always looking for new ways to raise donations, Koosman one year sold Christmas trees, wreaths and holiday pots. Financially, "it did not go good," Koosman said. By Christmas, he was stuck with half the greenery.

But one purchase made it worth it.

Angela Koosman had just moved to the Willmar area and went to the Christmas lights with her father. The "pretty girl" bought a holiday pot, Chad Koosman said, paying with a check. After some sleuthing, Koosman, who owns a lawn care business, realized that Angela lived next door to one of his clients.

"It must have been a God thing," he said, because not long after, that client showed up to buy a Christmas tree. Chad asked whether Angela was single.

They went on their first date on New Year's Eve. A year later, beside the lights and under the fireworks, Chad proposed.

The Koosmans now have a ginger-haired 8-month-old daughter, Sophia, whom they dress in elf diapers. For this year's show, Chad built a 50-foot pink and blue tree in her honor.

Looking out the window, she reaches for the lights.

"Celebrate the Light" has become a key backdrop in friends and strangers' stories, too. Elderly couples, hospice patients and school kids visit. "It's special that we're not only raising money," Chad said, "we're getting families back together and showing them the real meaning of Christmas."

In November, before the show was officially lit, Scott Martin, 31, brought his girlfriend by. They drove through the tunnel and parked.

"I had told Chad, when you hear the second door shut, hit the lights," he said.

A sign, which Martin had helped craft, lit up: "Will U merry me?" His friends razzed him for the typo, but the spelling was deliberate, Martin said, laughing. Why not salvage a sign Chad already had?

"He can make anything happen," Martin said, of Chad. "He just went above and beyond what I expected."

This year's display took 900 hours to set up. (It helps that his business is seasonal, Chad noted.) He and a computer-savvy friend sat in a truck for three nights straight, programming the 32 "Light-O-Rama" boxes that make the lights bounce to the music. The lines lead to a single laptop, in charge of it all.

Each year, more

Just after 5 p.m. on a recent Monday, Merlin and Elda Mae Krupke parked their Toyota in the Koosmans' driveway, the show's glow illuminating their smiles.

Elda Mae had heard about the lights at the hairdresser, so after an afternoon of playing cards, the pair drove down from Paynesville.

"She said, 'You've gotta come down and see this,' " Elda Mae Krupke said.

"It's beautiful," Merlin added, staring at a tall, flashing tree. "I can't see how that tree can have all those lights and change colors."

Each night, couples like the Krupkes circle the Koosmans' long driveway, which they share with one neighboring house, park and dim their headlights. But the display has become more than lights. On weekends, there are kids' movies, cookie decorating and photos with Santa Claus.

In the early days, the Koosmans told people to turn on their dome light to get an escort to their house's bathroom — "the dumbest thing we ever did," Chad Koosman said. Now they rent port-a-potties. Chad used to flood the ice rink — yes, there's also an ice rink — with a garden hose, then dunk it in the hot tub when it would, inevitably, freeze. Now the Spicer Fire Department comes by with its truck to fill the rink.

The fundraising, too, has become more sophisticated. Koosman solicits corporate sponsors to help cover some expenses and match a few nights' donations. On Christmas Eve, for example, CHS Inc., where Angela's father works, will match the kettle up to $10,000.

There are drawbacks to such a big production. In the summer, the six telephone poles required "are kinda ugly," Koosman said, "but it's well worth it for the Christmas lights." The neighbors, Harlan and Jennifer Davenport, have been good sports, cutting back branches to make way for the school buses and promoting the event on Facebook. Harlan Davenport always puts up his own lights, trimming about 20 trees. The crowds are "pretty overwhelming at this point," he said. But the couple endorse the show.

"Everybody asks us if we get tired of it," he said. "No, it doesn't bother us."

The Koosmans have made "the personal commitment to each other" that they won't stop until they've raised $1 million, Angela said.

"If it's up to my husband, we will continue to grow," she said, laughing. "But it's just gotten so big. I don't know how much bigger we can get on our own."

Jenna Ross • 612-673-7168