Here's something interesting: Sonia Sotomayor was the subject of a roll call vote in 1998, when she was confirmed to her current position the 2nd Circuit. The overall vote was 67-29 in favor of confirmation, with 4 Senators not voting. All Democrats voted in favor of Sotomayor (although three did not vote), while Republicans opposed her by a 29-25 majority.
Among those Senators who are still in the chamber today, however, Sotomayor's margin of confirmation was a bit more comfortable: 36-11. CORRECTION: The list below omits John Kerry, who also voted in favor of confirmation. That makes the total 36-11, rather than 35-11 as originally reported.
How Current Senators Voted on Sotomayor
Asterisks indicate members of the Senate Judiciary Committee. Note that the ranking Republican member, Alabama's Jeff Sessions, voted against Sotomayor in 1998, although Orrin Hatch, who was then the Committee chair and remains on the committee today, voted for her.
It seems to me that with this pick, Obama may be trying to carefully calibrate the amount of Republican resistance: enough that there's a chance that they'll do something that makes them look silly, but not enough for them to seriously threaten Sotomayor's nomination with a filibuster.