I say work against the Rhinos in Republican primaries, but then support them if they win the primaries. Except in Republican primaries and when directly communicating with Rhinos to affect their votes, remember Reagan’s 11th Commandment.
Most Rhinos are better than Marxist Democrats, when the two are the only choices. Also, in areas where no conservative has a ghost of a chance of winning, a Rhino (if he or she has some chance of winning) may be preferable to an unelectable conservative in a Republican primary. PA may fall into this category, I do not know.
Obama’s Marxism needs to be blunted, even if it means holding your nose and voting for a Rhino.
Reagan's Eleventh Commandment only applies to other Republicans, not necessarily former Republicans who have become independent and unaffiliated.