ESCR is a significant move in the wrong direction. It is an opening door. It is anti-life (in every sense) and irreconcileable with the concept of human dignity. While everyone is focused on abortion, ESCR is a giant step toward making human rights even more a matter of political influence (or scientific interest), rather than a matter of Objective Truth (all Men are created equal). For decades we've been working to set up a roadblock, a checkpoint, to try and slow down or stop the Mac Truck of abortion (which is a very good thing), but we may end up slowing the truck down a little while letting the Freight Train of ESCR blow right by us.
If ESCR ends up gaining wider political and social support, moderately restricting abortion will be cold comfort in the end. In the words of Aleksandr Solzhenitsyn, they offer a kopek in change for a ruble. ESCR is handing our embryos over for "scientific research" to modern day Dr. Frankensteins who believe nothing should stand in the way of their scientific curiosity, most especially a quaint little historical relic like "ethics". It has started with embryos, but there is no reason to suppose that it will end anywhere at all. Why would it? Why in the world would scientists suddenly begin to draw arbitrary moral lines when there is still funding to be had?
McCain/Palin need to have their feet held to the fire on this glaring inconsistency (for now the GOP seems to get it, at least in print). We need to jam our foot against this opening door while we have a chance.
That said, Obama is the most enthusiastic supporter of ESCR in the race. At least he's consistently anti-life.