toss up

30 Moby Thesaurus words for "toss up":
      blind bargain, borderline case, chance, chance at odds,
      contingency, double contingency, even break, even chance,
      fair shake, fifty-fifty, gamble, gambling chance, guess,
      half a chance, matter of chance, odds, open question,
      piece of guesswork, potluck, potshot, question, random shot,
      sight-unseen transaction, sporting chance, square odds, standoff,
      toss, touch and go, undecided issue, wager