Chopra leads at 7-under 135 overall, while both Poulter and Chan failed to finish the second round because of darkness.
"I started out yesterday edgy with all the delays, but came out today feeling better," Chopra said. "This is the best I have felt about my game in a long time."
About two-thirds of the field at the field was still on the course when play was halted after lightning caused delays for the second straight day.
Phil Mickelson, who shot 69 on Thursday, was 1 under after completing four holes of the second round. Padraig Harrington (69) is 1 over overall, while Geoff Ogilvy (74) is 2 over.