When the fourth and final round resumes, Curtis will try for his second PGA Tour victory. He won the 2003 British Open.
"I don't want to go to sleep tonight like I've got it won because I still have six 1/2 holes to go," Curtis said when play was stopped. "It's not going to be easy, but I have to go to bed confident and know that I can do it. You're always afraid something isn't going to work. Hopefully (a win) will be the start of something good for me."
Since his British Open win, Curtis has missed 32 cuts in 66 PGA tournaments. He is 23-under-par through 11 holes at the Booz Allen.
Ireland's Padraig Harrington is alone in second place at 15-under through 13 holes of the fourth round.