I'm not very knowledgeable about these things, but I can't imagine it making a huge difference for this show. I think the people who want to see it will do so either because they have heard about it and want to see the play, or because of Williams or Daniels. I don't think it's one where someone hears it was nominated for a Tony and decides to see it where they wouldn't have before. I would venture a guess that musicals are more likely to enjoy such a boost, but even then, I imagine it's not huge. (Of course for musicals, who knows if this year will be different since no one is waiting to see what will win, and no one can get tickets for the presumptive winner... Maybe nominations will be a factor.)
This is just a nominally-educated guess from word of mouth and such. There are others around here who know way more than I.