If Clinton announces that she will run for president very early next year, that should call for at least a few major Republicans to make clear that they are running as well. It wouldn't be in the GOP's best interests to allow Clinton to be the only voice on the campaign trail, since that would surely augment her current advantage over Republicans. On the other hand, if some Republicans do announce their candidacy in roughly the same time period as Clinton is expected to, it makes clear to the general public that there are options aside from her.
Agreed. If Hilary is announcing in January, I'd be shocked if there were no major Republicans declaring their candidacy by the middle of April.