The Vegas Golden Knights are now co-favorites to win the Stanley Cup, according to the Westgate Sportsbook. That's a stunning turnaround considering the NHL's newest expansion team opened the season with 200-1 odds.

As of Wednesday, the Golden Knights are tied with the Nashville Predators with 4-1 odds.

The Golden Knights became the first team in the Stanley Cup playoffs to clinch a ticket to the second round after sweeping the Los Angeles Kings in four games. Vegas became the first franchise in NHL history to sweep a postseason series in its inaugural season.

Over the summer, Vegas management had tempered expectations. General manager George McPhee publicly declared a goal of making the playoffs in the team's third season and winning a Stanley Cup in six.

"We don't have high expectations for this year," owner Bill Foley told ESPN in August. "We're going to be competitive. If we're going to lose a game, we'd like to lose by a goal or two, not lose by five or six. We don't want to be a walkover team. We want to be competitive. We want to be entertaining on the ice. We want to score some goals."

Instead, the Golden Knights have been one of the biggest success stories across all sports. Vegas became the first NHL team to make the postseason in its inaugural season since 1979-80, when the Oilers and Whalers reached the playoffs after joining the league as part of its merger with the WHA. The Oilers featured Wayne Gretzky, while the Whalers had Gordie Howe on the roster. It was also a time when just five of the league's 21 teams didn't make the playoffs.

Station Casinos in Las Vegas are among those trying to capitalize on the Golden Knights phenomenon, offering free bets on the team to casino loyalty members who come in to one of their establishments on April 23.

Of the 64 expansion teams among the four major U.S. sports leagues since 1960, no team posted a winning record in their first season -- until Vegas.

The Golden Knights will face the winner of the San Jose Sharks and Anaheim Ducks series in the next round. San Jose leads the series 3-0.