Hillary Clinton
Hillary Clinton at a town hall meeting hosted by CNN at the University of South Carolina in Columbia. Scott Olson/Getty Images

While Americans are no doubt transfixed by 2016's particularly unpredictable election, many outside the United States are closely following the primaries as well, and not for the reasons you might expect. While it is illegal to bet on elections across most of the country, outside of the U.S. people are free to bet as they please, and a whole lot of money is riding on the election's outcome.

According to odds analysis site OddsShark, at least twice as much money has been wagered on this election then in 2012, though that is perhaps not surprising considering the lengthy primary races on both sides. President Barack Obama ran unopposed in the 2012 Democratic primary, and this election cycle has featured outlandishly entertaining moments.

Where is that money going? In short, gamblers have been betting on the outsider long shots-turned-contenders: businessman Donald Trump and Vermont Sen. Bernie Sanders. Trump, the current Republican front-runner, has been the most popular play for bettors by far at this point in the election, after a drastic improvement in his odds from 150-1 to 3-1. Meanwhile, a massive amount of bets were placed on Sanders when the candidate stood at 20-1 odds. However, Sanders has become more of a long shot as Democratic rival Hillary Clinton has begun to pull away in the delegate count.

Speaking of Clinton, despite being the odds-on favorite to win the 2016 election since the beginning of the cycle, she has not been a popular play for betters.

"People like to go for the big payout," Kevin Bradley, sports book manager for Bovada, told OddsShark. "We had Trump at 150-1 when we first posted odds on this around a year-and-a-half ago. Every $10 is $1,500. It doesn’t take big money for that to add up pretty quickly.”

All the money being wagered on Trump and Sanders makes the pair the nightmare scenario of nominees for bookmakers, whereas Clinton and Florida Sen. Marco Rubio would be the most risk-free pairing.

As for Trump, his odds just keep getting better. In the Nevada primary Tuesday, Trump won with nearly 46 percent of the vote. Rubio was a distant second with just under 24 percent, and Cruz placed third with over 21 percent. Following Nevada, Trump has a large lead in the delegate count, with 79. Texas Sen. Ted Cruz is in a distance second with 16 delegates, and presumptive establishment favorite Sen. Marco Rubio of Florida has 15 delegates. To secure the nomination, 1,237 delegates are needed, and Trump is on pace to hit that target number with relative ease, according to analysis by the Washington Post.

While bookmakers might be spared a Sanders nomination, they may soon have to face the reality — and subsequent payouts — of a Trump nomination.