Better to keep the conservatives on your side if you want to remain a Republican. If they are so afraid of liberal block voters, maybe they should just switch their membership.
Just what makes them think Americans wish socialism, wish for America to be less safe, wish for America to sell off its secrets to the highest bidder?
Maybe we need term limits for senators. Apparently living in Washington is very detrimental to the moral fiber of our representatives. Power is very corrupting - especially for senators in the "club environment".
Once they take office, I find that many conservatives "move to the middle" in a bid, sometimes fruitless, to attract "moderate" and some liberal voters for the next election. They call it expanding their base. Senator Lugar of IN, for instance, has been very successful with that type of liberal outreach.