I think you’re right about Holder. He’s got too much visibility. Watch for a stealth candidate, someone who will look okay to both sides, but once in will slide over to the liberal side when important issues (abortion, 2nd amendment, etc.) come up. The sign will be when the ‘Pubs start making statements that effectively say, “this one is okay, about the best we can hope for from Obama”. Then the vote will be something like 99-0 in favor, and the Constitution as we know it gets flushed.
Until a candidate comes up that looks really good,then the Republicans just need to continue to delay the nomination. The last thing we need is another Obama pick. He has a way of picking the worst of the worst.