I don't thinkk its surging to the left.
I think there are a lot of "leaders" who have drifted leftwards, but their constituency is wondoering what in the world the people they elected to office think they are doing.
Hegel, Snowe, Chaffee, McCain, Romany, Giuliani, are counterbalanced by the mass of the Republican constituency which is far more conservative than they. There are still Hunter, Kyl, King (Of Iowa), Gingrich, Tancredo, etc, which represent traditional Republican philosophies.
But if the Repubs nominate a RINO nationally, and this could happen through the mechanics of the nomination process, despite the actual views of the majority of Republicans, then the Republican Party is pretty much finished as a conservative party or party of opposition.
It will instead become Democrat Light - a catch-up liberal party with no real support among the public.
The American Republic in all its history has NEVER faced the dangers it is facing now.