My forecast: The only “single-digit opposition” that Roberts is going to encounter is in the Senate Judiciary Committee–and that’s because there are only eight Democrats on the Committee. At this point, I think it likely that Roberts gets confirmed with somewhere between 55 and 70 votes. It’s possible that he’ll get more than that, but I see no reason to expect it.
Senate Democrats are walking the same tightrope that Tom Daschle fell off of. Their entire campaign and fundraising apparatus is pushing them hard left, at their electoral peril.
As a Supreme Court advocate, Roberts knew where to look for the five votes he needed. In his upcoming hearing, in order to get to 51, all he needs to do is hold his Republican base of support. The riskiest course of conduct would be for him to try to get a landslide vote: an extravagant effort to appease Senate Democrats (probably futile, in any event) could imperil the support of conservative senators.
I see the target as 51, rather than 60, because I think there is no prospect of a Democrat filibuster: The Democrats know that a filibuster of Roberts’s confirmation would trigger cloture reform.