28 U.S.C. § 3702 : US Code - Section 3702: Unlawful sports gambling

      It shall be unlawful for - 
        (1) a governmental entity to sponsor, operate, advertise,
      promote, license, or authorize by law or compact, or
        (2) a person to sponsor, operate, advertise, or promote,
      pursuant to the law or compact of a governmental entity,

    a lottery, sweepstakes, or other betting, gambling, or wagering
    scheme based, directly or indirectly (through the use of
    geographical references or otherwise), on one or more competitive
    games in which amateur or professional athletes participate, or are
    intended to participate, or on one or more performances of such
    athletes in such games.