Besides heavily sweet wines like port or sauternes, there's another, somewhat obscure option. Since OP is in New England, he may be able to find a Russian grocery nearby, and if that grocery has a liquor license, they are guaranteed to carry some Georgian wines. Many of those wines, while produced with the same process as a conventional dry red wine, have noticeable natural sweetness. Try Kindzmarauli or Khvanchkara (and don't worry: nobody, but native Georgians, can pronounce those names). The only problem is that sometimes you end up with a fake (distribution channels are not reliable enough to prevent this), but the real thing is very likable.