The Seattle Seahawks didn’t need 12 men Sunday night.

Eleven did just fine, thank you.

Jumping on the Denver Broncos in the first 12 seconds (naturally), they romped to a 43-8 victory in Super Bowl XLVIII at MetLife Stadium, an emphatic statement that in this pass-happy era, defense can win championships, even over a record-setting offense and legendary quarterback.

No, the Broncos didn’t have to put up with the raucous “12th man” atmosphere at Seahawks home games, but this was a dirty dozen in other ways. Seattle scored 12 seconds into the first half on a safety, then did the same thing to open the second half when Percy Harvin returned the kickoff 87 yards for a touchdown and 29-0 lead to all but cue the championship parade.

“All our players know we take this trophy back to the 12th man,” Seahawks coach Pete Carroll said. “An unbelievable spirit.”

Freshly anointed MVP Peyton Manning of the Broncos never had a chance, starting with the first play of the game when the snap eluded him for the safety and including an interception returned 69 yards for a 22-0 second-quarter lead.

“I’m disappointed for our entire team,” Manning said. “We worked hard to get to this point and overcame a lot of obstacles to be here. To finish this way is very disappointing.”

The NFL’s No. 1 defense, the “Legion of Boom,” looked the part, making Denver’s No. 1-ranked offense a shell of itself, causing two first-half turnovers and not allowing a first down until well into the second quarter.

“All those people who say defenses win championships can go ahead and gloat for a while, because it’s true,” Carroll said.

Denver (15-4) became the first franchise to lose five Super Bowls, having also won two under John Elway. Seattle (16-3) improved to 1-1 in Super Bowls.

“Tonight was just unbelievable,” Seahawks quarterback Russell Wilson said. “The thing you want to do at the end of the season is you want to play your best football, and that’s what we did tonight.”

The lack of a competitive game was a sour note to cap an otherwise successful Super experiment by the NFL, which took the risk of placing its signature spectacle in a cold-weather, outdoor venue for the first time. A week that began under frigid conditions warmed with each day, drawing throngs to “Super Bowl Boulevard” along Times Square.

Broadway Joe Namath, wearing a massive fur coat, conducted the coin toss (including once prematurely, when it was intercepted by panicked referee Terry McAulay). At kickoff, it was a downright balmy 49 degrees, 10 above the coldest Super Bowl ever and warmer than in both Seattle and Denver. A crowd of 82,529, including NFL Commissioner Roger Goodell — seated outdoors — was grateful. As luck would have it, an overnight snowstorm was expected to follow.

Manning, in the eyes of some needing this victory to cement his legacy, floated a second-quarter pass over the middle that was intercepted by safety Kam Chancellor, setting up a 1-yard touchdown run by Marshawn Lynch to make it 15-0.

Denver seemed to awaken on the next series, reaching the Seattle 35, but defensive end Cliff Avril hit Manning as he released. Linebacker Malcolm Smith gobbled up the pass and returned it 69 yards for a score. Smith, who also recovered a fumble, was named MVP. Manning, meanwhile, looked so helpless, you might have thought he was facing the Florida Gators. He finished by passing for 280 yards on 49 attempts and 34 completions — the last stat a hollow Super Bowl record.

On and on it went. Denver averaged 37.9 points per game and managed eight. Denver averaged 457.3 yards per game and managed 306. The fewest points the Broncos had scored before Sunday was 20.

“They’re a great defense,” Broncos coach John Fox said. “It didn’t surprise me. I thought they were very big, very fast. They did an outstanding job.”

The question now surrounds Manning, 37. Was this his last game? He doubts it, but also said if the doctor expresses reservations about his surgically repaired neck, “It wouldn’t even be up for discussion” and he would retire.

His counterpart, cool, 25-year-old Wilson, was solid (18-for-25, 206 yards, two TDs, 123.1 rating). He thoughtfully dumped out half of the Gatorade before he and tight end Zach Miller tossed the rest on the feisty Carroll.

At 62, Carroll became the third-oldest Super Bowl winner behind Tom Coughlin and Dick Vermeil. He also joined Barry Switzer and Jimmy Johnson as the only coaches to win a Super Bowl and a national title in college football.

The “X” factor was Harvin, the former Florida Gators receiver and prized acquisition who was relegated to only one regular-season game following hip surgery. Denver was gashed by two early end-arounds by Harvin for 45 yards before the parting-of-the-seas kickoff return up the middle.

From there, heavy doses of that Seattle favorite — Starbucks — helped neutral viewers get through all the time that remained.