Creamer, seeking her third LPGA win this season, is at 18-under 195.
The 21-year-old Creamer, of Windermere, Fla., had a stunning 11-under 60 in the first round -- a stroke off the tour record -- and a 65 in the second.
Eun-Hee Ji carded a 68 to hold second place at 14-under 199.
Rachel Hetherington (67) is third at 11-under 202.
"I only shot 1-under, but at the same time I have a pretty significant lead going into tomorrow and it's only 18 holes," Creamer said.
"Winning wire-to- wire, that's difficult to do. There is a lot of pressure on you in that situation, especially the first day shooting 60. Anything higher than that, people think, what's going on?"