Time for all good men to come to the aid of their country

The phrase "It's time for all good men to come to the aid of their country" Where is it from and where can I find the full script?

Usually rendered "Now is the time for all good men to come to the aid of the party" I'm afraid it has no origin in the works of some crowd-stirring orator, but is nothing more than a typing exercise (along the lines of the quick brown fox...) invented by one Charles E. Weller.

There is no full script.

DFG