Way back in 1998, John McCain pushed to eliminate all gambling on amateur sports, including college and Olympic games. Vegas fought it and compromised with no gambling on the Olympics. NCAA football and basketball betting stayed.

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Last year, the Nevada Gaming Control amended the gaming rules of the state to allow betting on the Olympics. Odds for the higher-profile sports have come out:

  • Phelps is the favorite in the 100-meter butterfly and 200-meter fly at 6/5.
  • Novak Djokovic is the bigger favorite in men's tennis than Serena Williams is in women's at 6/5.
  • Usain Bolt is favored in the 100-meter at -190, a $190 bet is needed to win $100.
  • Ryan Lochte will be a part of the 4x200-meter freestyle and is the -250 favorite.
  • Almaz Ayana, a runner from Ethiopia, is a -1200 favorite in the women's 5,000-meter.
  • Men's rugby favorites, All Blacks, sit at 11/5 odds.
  • Russia's synchronized swimming duet and team sit with -800 lines for both.

The U.S. is favored to take home the most gold, the over-under it 43.5 and China's is 35.

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