The Washington Capitals were on the power play Wednesday night, and at Capital One Arena, Danny Provencher sat transfixed. Provencher, a 30-year-old from Manassas, Va., was glued to the Jumbotron, watching as more than 2,000 miles away, Alex Ovechkin scored to give the Caps a 2-1 lead.

Then Provencher, and the thousands of Caps fans who surrounded him, stood to their feet and roared.

“It was amazing,” Provencher said after the goal. “This doesn’t happen to Washington sports teams. This is amazing.”

According to the Capitals, more than than 14,000 fans turned out Wednesday night to catch Game 2 of the Stanley Cup finals, watching together on the arena’s big screen.

The multitude of fans, which included Provencher, gathered together here for what would be the team’s first Stanley Cup finals win in franchise history, a 3-2 victory over the Vegas Golden Knights that evened the series.

It was a raucous May bash, held around a sheet of frozen ice. It was a rowdy and joyful crowd, absolutely living for every shot, delighting completely in this moment they had waited so long for.

Who would come here, to watch a game played so far away? Families. Long-time pals. Buddies, back home from college for the summer. Sure, the Caps weren’t around, but it wasn’t like this was an empty arena. Everyone here was surrounded by friends.

“Everybody seems to just want to celebrate with each other,” said Meggie Rock, 20, a college student from Maryland. “Everybody’s looking to kind of hype each other up. It’s good feelings, all around.”

Before the puck dropped, the crowd booed during Vegas’s pregame show. They booed Imagine Dragons, which was very funny. It was a loud and lovely night, as a long-suffering fan base cheered on its home team.

“Caps fans identify with each other because of the struggles that they’ve experienced,” Dan Curry, a 36-year-old from Maryland, said as he waited to get into the arena Wednesday night. “The disappointments every year. The expectations and the hopes.

“But I think part of it is the excitement, but part of it is to be able to be with other people who have been through the same mourning process every year. We’re definitely a family.”

There was $4 beer. Beach balls. In-seat dancing. Capital One cheer posters. A large bird mascot. A dog hanging outside the arena before the game.

“It’s camaraderie,” said Michael Robertson, owner of Ovie the Bulldog. “A lot of these people have been fans for years and decades. And have suffered together. We’ve all done the march of sadness out, when the Pens beat us or whoever ended our run. We’d have to just shuffle out, upset, mad, disappointed in the team.”

Then came this year, and a surprising playoffs run. The Caps made the finals, and Robertson, 47, traveled from California to Washington with Ovie, the 8-year-old bulldog Robertson has had since he was just a pup. They had arrived in the city earlier in the day, and Robertson wasn’t sure whether he and his pup would show up Wednesday night.

“I said, you know what, it’s the Stanley Cup,” Robertson said.

So here was Ovie, lounging outside the arena, stonewalling a Washington Post reporter who asked the doggo about whether he had any predictions, or a message for Bark-Andre Furry, his Vegas counterpart.

According to a team staffer, about 11,000 packed the arena for the Capitals’ Game 7 Eastern Conference finals road win over the Tampa Bay Lightning, a crowd that hugged and cheered and spilled out into the streets. And when the Stanley Cup finals opened in Las Vegas on Monday night, about 12,400 fans filled the visiting team’s arena in Washington.

For the sake of comparison, the Capitals announced a crowd of 16,325 spectators for Ovechkin’s NHL debut, at what was then known as MCI Center, according to Tarik El-Bashir’s 2005 story in The Post. That season, the Capitals’ average attendance was about 13,900. Okay, a more recent example: The Nationals played the Orioles on Tuesday in Baltimore, a 3-2 win. The crowd at Camden Yards was 13,935.

Provencher could remember the Caps’ last trip to the Stanley Cup finals in 1998. He was just 10 years old, watching in his Virginia living room with his dad.

“We freaked out,” Provencher said.

He stood in that same living room with his father, when the Caps beat Tampa Bay in Game 7 this year. But when he found out about the viewing parties, he decided he had to be there. He was out of town for Game 1 of the finals, but on Wednesday night was in the arena as the third period wound down and the fury was unleashed.

The arena erupted late in the third, as Capitals goalie Braden Holtby robbed Alex Tuch of what would have been a game-tying goal, then erupted again and again, when the replay aired. The final horn sounded, and this Caps crowd went bonkers around their home ice.

Arms flew up in the air and trash sailed down to the ice. There were (at least) three shirtless dudes, according to my less-than-stellar notes.

The crowd streamed out into a light rain, and some would stand on the steps of the National Portrait Gallery to chant “We want the Cup!” Before they all left the arena, though, an announcer shouted “Do you believe?” As if he even had to ask.

Immerse yourself in the Capitals’ postseason with The Post’s coverage of the Stanley Cup playoffs: