vim extracting first column (space delimited)

Just figured out how to extract a single (first) column from a file containing text

:%s/^\(\w\+\)\.\*/\1/g

I am sure there is a better way to do this but this is best I can get for now. I don't like the excessive escaping vim requires in regex.

PS: Just figured out that you have to have:

:set nomagic

for the above subsitution to work.