Sure! The goal of the month is to see if you can reach 50,000 words though so even if you have a good bit written on the piece already, you will still need to write 50000 in the month of November. Say you already 2,000 words written before midnight tomorrow, your final word count will have to be 52,000.

If you want the file to be converted to the Nanowrimo section of the site, just ask Coen and he should get it set up. I believe he had to do the same for me last year.