[socalstanfan1]

I don't see how this ends well for the Republicans.  Their hold on the Senate is tenuous to begin with, and in recent presidential-year elections the Democrats have done a much better job of turning out the vote.  The Republican party is looking incredibly fragmented, which generally doesn't bode well for turn-out-the-vote efforts: nominate a centrist, establishment candidate, and the far-right turnout is tepid (see McCain and Romney election bids); nominate the far-right candidate and lose the center, plus pretty much any moderate independent voter.  Then, add in a Senate bid to obstruct the nomination of a Supreme Court justice (and that is certainly how I would spin it if I'm a Democrat, as "obstruction"), and you've given the Democrats a prime issue for rallying their own base. 

Also, I doubt that the majority of Americans see Sotomayor and Kagan as "radical" or "out of the mainstream" justices.  Referring to them in that way, particularly Sotomayor, allows the Democrats to drive home the point that it is the Republicans who are out of step with the general electorate, and as a party out of step with the fastest growing sector of the electorate.  Given narrowness of the Republican path to the White House, the GOP may well stop the nomination of another Obama justice, but at the same time lose both their latest shot at the White House, as well as their hold on the Senate.

[socalstanfan1]

I don't see how this ends well for the Republicans.  Their hold on the Senate is tenuous to begin with, and in recent presidential-year elections the Democrats have done a much better job of turning out the vote.  The Republican party is looking incredibly fragmented, which generally doesn't bode well for turn-out-the-vote efforts: nominate a centrist, establishment candidate, and the far-right turnout is tepid (see McCain and Romney election bids); nominate the far-right candidate and lose the center, plus pretty much any moderate independent voter.  Then, add in a Senate bid to obstruct the nomination of a Supreme Court justice (and that is certainly how I would spin it if I'm a Democrat, as "obstruction"), and you've given the Democrats a prime issue for rallying their own base. 

Also, I doubt that the majority of Americans see Sotomayor and Kagan as "radical" or "out of the mainstream" justices.  Referring to them in that way, particularly Sotomayor, allows the Democrats to drive home the point that it is the Republicans who are out of step with the general electorate, and as a party out of step with the fastest growing sector of the electorate.  Given narrowness of the Republican path to the White House, the GOP may well stop the nomination of another Obama justice, but at the same time lose both their latest shot at the White House, as well as their hold on the Senate.