The Washington Post has just published a longer version of my previous post on how liberals can reclaim the Constitution. It's available here.
The point of the piece is not that liberals should all become Scalia-style originalists and start talking like movement conservatives do. Rather, it's that liberals should simply reject the false dichotomy between originalism and a living Constitution.
Accepting that opposition as the proper frame for debate just locks liberals into a clever rhetorical strategy created by movement conservatives in the 1980s, who wanted to put themselves on the side of the American constitutional tradition, and liberals on the outside looking in. Contemporary liberals should reject that invitation. The American constitutional tradition, understood in its best light, is a liberal egalitarian tradition.
Franklin Roosevelt, Hugo Black, and the Warren Court had no problems with proudly invoking the founders and showing why liberal projects were faithful to the constitutional project the framers began. We shouldn't have any problems with that approach today.