David Purdum says on Daily Wager that Las Vegas sportsbooks aren't allowing betting on Game of Thrones since the outcome has already been determined. (1:09)

Winter has come and gone, and bettors in the United Kingdom have overwhelmingly picked their king: Bran Stark is the odds-on favorite to rule Westeros at the end of the final season of "Game of Thrones."

The wildly popular HBO series kicks off its last season Sunday with infinite potential outcomes for who will end up on the Iron Throne. It has generated significant betting action at U.K. sportsbooks and given oddsmakers fits.

"The betting we've seen on the final season is unprecedented for a television series in [U.K. bookmaker] Paddy Power history," Amy Jones, a public relations manager for Paddy Power, told ESPN in an email. "We believe, because it's the finale, that the hype is bigger than we've ever seen on TV betting -- also, because of the nature of the show."

In August, Paddy Power opened Bran Stark at even money to finish atop the throne at the end of the series. He's now 4-5 at most U.K. bookmakers, and, yet, he's also 2-1 to die during the season.

The largest bet Paddy Power has taken on "Game of Thrones" since last August was four figures. The majority of the wagers, however, are in the £1-50 range, according to Jones.

An array of betting markets is available on the show: everything from which character will die first to who will say the first line. Dozens of characters are listed on the odds to win the throne, many with odds in the single digits. Different plot theories pop up regularly on the internet, forcing oddsmakers to keep a close eye on the betting action.

"If we see a real rush of bets on Khaleesi to rule at the end of the season, we will cut her price accordingly," Jones added.

"Pricing up has been very difficult," Joe Crilly, spokesman for William Hill in the U.K., wrote in an email to ESPN, "as we know from the show that literally anything can happen. There are thousands of theories on the internet, which we have tried to avoid so our judgement isn't clouded. Things that have happened in the series have been hinted at in previous episodes so an in-depth knowledge of the show has helped a lot."

Traditionally, legal U.S. sportsbooks have not offered betting on TV shows, due to fears of inside information being leaked. In 1980, late Las Vegas bookmaker Sonny Reizner posted odds on "Who shot J.R.?" for the popular prime-time drama "Dallas." Regulators stepped in and forced Reizner to take the odds off the board.

The American bookmaking industry is evolving, though, with nine states now offering legal sports betting and dozens more examining the issue. In February, New Jersey sportsbooks, for the first time, took bets on the Academy Awards. More than $747,000 was bet on the Oscars with New Jersey's sportsbooks, which are not offering odds on "Game of Thrones."

The popular Jon Snow and Sansa Stark, sister of Bran, are among the top contenders to rule Westeros. Snow is 5-6 to survive the season and also 5-6 to be eliminated. The Night King is 11-1 to rule Westeros.

Fortunes look bleak for Queen Cersei Lannister, who is a massive 1-50 favorite to perish in the final season.