I know it is possible for twins to be born on successive days, one shortly before midnight, and one shortly after. In fact, my son went to school with just a set of twins. But two days apart? Is that possible?
In the vital records of Livermore, Maine, the births of Polly and Patty Benjamin are recorded on October 2 and October 4, 1792. The birth dates of their siblings make it unlikely that the year is recorded wrong for each of them. They are indeed separate people; Polly married a Samuel Ames, and Patty, AKA Martha, married Israel Washburn, the author of the 1858 history of Livermore, who calls Polly and Martha twins in his book.
The obvious answer is a scrivener's error - but that seems to me unlikely, given that the births are recorded in the same hand on two adjacent lines.