NEW YORK >> Flynn the bichon frise won best in show at the Westminster Kennel Club on Tuesday night, a choice that seemed to surprise almost everyone in the packed crowd at Madison Square Garden.

Fans who had been loudly shouting for their favorites fell into stunned silence when judge Betty-Anne Stenmark announced her decision.

No matter, the white powder puff was picked and walked off as America’s top dog.

Guided by expert handler Bill McFadden, Flynn beat out Ty the giant schnauzer, Biggie the pug, Bean the Sussex spaniel, Lucy the borzoi, Slick the border collie and Winston the Norfolk terrier.

“It feels a little unreal,” McFadden said. “I came in expecting nothing except hoping for a good performance, and I think I got it.”

Upsets by underdogs are common on the green carpet of the Garden — inside dog fanciers indeed fancied Flynn, but the people sitting in the stands were obviously pulling for other dogs.

Cheers of “Let’s go, Biggie!” bounced all around the arena for the popular pug. Bean was a clear crowd favorite, the way he sat up straight on his hind legs and begged judges for the biggest treat in dogdom.

Ty came into this competition as the nation’s No. 1 show dog last year and finished as the runner-up. He endeared himself to spectators by jumping up and putting his front paws around handler Katie Bernardin after winning the working group earlier in the evening. Slick and Lucy also drew applause.

Almost 6, Flynn was the fourth-ranked show dog in the country last year. Even so, he wasn’t the hot dog when this night began.

Flynn posted his 42nd career best in show victory in what was almost certainly his last event before retiring. McFadden says it takes two hours to cut his fur before being presented, and not a hair — or step — was out of place for his finale.

The famed JR was the only other bichon to win Westminster, in 2001. McFadden has enjoyed success at the Garden, having guided Mick the Kerry blue terrier to the title in 2003.

Flynn won’t get much rest before beginning his victory lap. Today’s schedule includes visits to the morning TV news shows, a steak lunch at Sardi’s, a trip to the top of the Empire State Building and a walk-on part at the Broadway musical “Kinky Boots.”

The Westminster-winning team gets no prize money. Instead, there’s a shiny bowl, lucrative breeding fees and, most of all, a lifetime of memories.

The 142nd Westminster event attracted 2,882 entries in 202 breeds and varieties. Among those who didn’t quite make the cut: face-licking Spicy Nacho the miniature bull terrier who drew laughs, just not the judge’s look.

Flynn made a goodwill gesture toward Stenmark upon meeting her, offering his paw as if to shake hands when she went down the line to review the final seven dogs.

His full name is Belle Creek’s All I Care About is Love, and this champion from the nonsporting group delivered a few minutes before it became Valentine’s Day.

“He has my heart,” McFadden said. “He is pure joy.”

The fans seemed to like Flynn, too, only they hollered a lot more for several others.

“He kept wagging his tail and that sold himself to me,” Stenmark said.