" I hope you can lend me twenty dollars," my friend said hopefully.
Many grammarians consider it incorrect to use " hopefully" to modify an entire sentence like the following:
Hopefully, we will be able to finish before the day is over.
Patricia T. O'Conner in Woe Is I says, " Join the crowd and abuse hopefully if you want; I can't stop you."
Constance Hale in Sin and Syntax says, " Grammarians, get a grip. Hopefully as a sentence adverb is here to stay."
William A. Sabin in The Gregg Reference Manual says, "...the use of hopefully at the beginning of a sentence is no different from the use of obviously, certainly, fortunately, actually, apparently, and similar words functioning as independent comments. These adverbs express the writer's attitude toward what he is about to say..."
Hopefully, the Grammar Doctor has cleared this up once and for all.