Lots of options via any of the big US hubs like NY, Philadelphia. Atlanta, Washington, etc.. As above, plug your dates into skyscanner and then filter down on things like price, airlines you might want to avoid, duration of travel with stop-overs. You want enough time for a stop-over to make your way to the departure terminal / gate, but don't want to be hanging around too long either.
RDU is a handy airport to get in and out of.