COLUMBIA, S.C. (AP) — Days of torrential rains kept much of South Carolina and its capital gripped by floodwaters Monday as emergency responders promised renewed door-to-door searches for anyone still trapped after a weekend deluge and hundreds of rescues. Heavy rain kept falling into the early hours Monday around the Carolinas from the storm that began swamping the Southeast late last week, part of an unprecedented low pressure system that dumped more than a foot of rain across South Carolina and drenched several other states. "The flooding is unprecedented and historical," said Dr.