Does having a number of benign polyps in the colon mean a larger chance of colon cancer?

Yes. Colon polyps predisposes to development of cancer, needs regular endoscopic removal and examination for cancer cells.Some of these polyp conditions runs in the family ( familial adenomatous polyposis ), then all the family members need to be examined march is colorectal cancer prevention month see your doctor.
Yes. Virtually all colon cancers arise from polyps and having polyps increases the risk of developing colon cancer.