People are probably already thinking about the possibility of a filibuster, just because.
But let's look at the lineup.
Thirty-six of the 67 Senators who voted for Sotomayor in 1998 are still in the Senate today. Those 36 are by no means bound to vote for her again. There are real differences between the 2nd Circuit and the Supreme Court, and there will be a significant paper trail to review. But politics being what it is, voting the other way is a difficult thing to do.
Thirty-six or so votes is a pretty decent base to start with. But we should also look at what happened to the other 31 votes Judge Sotomayor got in 1998.
Nine of those 31 votes were Democrats, whose seats are now occupied by other Democrats:
Joe Biden (D-DE), now replaced by his former chief of staff, Ted Kaufman (D-DE)
Dale Bumpers (D-AR), by Blanche Lincoln (D-AR)
Bob Kerrey (D-NE), by Ben Nelson (D-NE)
Frank Lautenberg (D-NJ), by Bob Menendez (D-NJ) (Remember? Lautenberg, Corzine, Menendez -- but wait, there's more!)
Daniel Moynihan (D-NY), now by Kirsten Gillibrand (D-NY)
Chuck Robb (D-VA), now by Jim Webb (D-VA)
Paul Sarbanes (D-MD), by Ben Cardin (D-MD)
Bob Torricelli (D-NJ), by Frank Lautenberg (D-NJ)
Paul Wellstone (D-MN), soon by Al Franken (D-MN)
Meanwhile, six of the 31 votes were from Democrats whose seats are now occupied by Republicans:
John Breaux (D-LA), by Diaper Dave Vitter (R-LA)
Richard Bryan (D-NV), by John Ensign (R-NV)
Max Cleland (D-GA), by Saxby Chambliss (R-GA)
Tom Daschle (D-SD), by John Thune (R-SD)
Wendell Ford (D-KY), by Jim Bunning (R-KY)
Bob Graham (D-FL), by Mel Martinez (R-FL)
But... a whopping 16 of the votes that came from Republicans came from seats now occupied by Democrats (or Bernie Sanders):
Ben Campbell (R-CO), now Michael Bennet (D-CO)
John Chafee (R-RI), now Sheldon Whitehouse (D-RI)
Dan Coates (R-IN), by Evan Bayh (D-IN)
Al D'Amato (R-NY), by Chuck Schumer (D-NY)
Mike DeWine (R-OH), by Sherrod Brown (D-OH)
Pete Domenici (R-NM), by Tom Udall (D-NM)
Rod Grams (R-MN), now Amy Klobuchar (D-MN)
Jesse Helms (R-NC), now Kay Hagan (D-NC)
Jim Jeffords (R-VT), by Bernie Sanders (I-VT)
Connie Mack (R-FL), by Bill Nelson (D-FL)
William Roth (R-DE), by Tom Carper (D-DE)
Rick Santorum (R-PA), by Bob Casey, Jr. (D-PA)
Gordon Smith (R-OR), by Jeff Merkley (D-OR)
Arlen Specter (R-PA), by... Arlen Specter (D-PA)
Ted Stevens (R-AK), by Mark Begich (D-AK)
John Warner (R-VA), by Mark Warner (D-VA)
And just two of the Republicans who voted for Sotomayor and then left the Senate left their seats in Republican hands... and one of them is the Murkowskis!
Bill Frist (R-TN), by Bob Corker (R-TN)
Frank Murkowski (R-AK), by Lisa Murkowski (R-AK)
Among those who voted against Sotomayor, we find 11 Republicans replaced by fellow Republicans:
Paul Coverdell (R-GA), now John Isakson (R-GA)
Larry Craig (R-ID), by Jim Risch (R-ID)
Lauch Faircloth (R-NC), now Richard Burr (R-NC)
Phil Gramm (R-TX), by John Cornyn (R-TX)
Chuck Hagel (R-NE), by Mike Johanns (R-NE)
Dirk Kempthorne (R-ID), by Mike Crapo (R-ID)
Trent Lott (R-MS), by Roger Wicker (R-MS)
Don Nickles (R-OK), by Tom Coburn (R-OK)
Craig Thomas (R-WY), by John Barrasso (R-WY)
Fred Thompson (R-TN), by Lamar Alexander (R-TN)
Strom Thurmond (R-SC), Lindsey Graham (R-SC)
And seven Republicans replaced by Democrats:
Spencer Abraham (R-MI), by Debbie Stabenow (D-MI)
Wayne Allard (R-CO), by Mark Udall (D-CO)
John Ashcroft (R-MO), now by Claire McCaskill (D-MO)
Conrad Burns (R-MT), by Jon Tester (D-MT)
Slade Gorton (R-WA), by Maria Cantwell (D-WA)
Tim Hutchinson (R-AR), by Mark Pryor (D-AR)
Bob Smith (R-NH), now by Jeanne Shaheen (D-NH)
Four Senators did not vote on her 1998 nomination:
Kit Bond (R-MO), who's still in the Senate;
John Glenn (D-OH), whose seat is now occupied by George Voinovich (R-OH);
Fritz Hollings (D-SC), whose seat is now occupied by Jim DeMint (R-SC), and;
Carol Moseley-Braun (D-IL), whose seat is now occupied by Roland Burris (D-IL).
Thirty-six who voted for Sotomayor in 1998, plus nine Democrats who replaced Democrats = 45.
Forty-five plus 16 Republicans who've been replaced by Democrats = 61.
Sixty-one plus seven Republicans who voted "no" but were replaced by Democrats = 68.
Sixty-eight plus one Democrat who didn't vote and was replaced by another Democrat = 69.
And that's not even getting to Murkowski, Bond, Graham, and Alexander, who are generally persuadable on nominations votes, at least in the abstract. Nor does it account for Mel Martinez, who on the one hand may be moved to support the first Hispanic nominee to the Court -- or may on the other be moved to exacerbate the political divide between Cuban-Americans and Puerto Ricans. Or, of course, he may opt to confound everyone and just oppose her nomination as a knee-jerk wingnut, and for no particular reason at all.
All told, though, I'm thinking... filibuster...? Not all that likely, though Senate comity will likely prompt Democrats to allow the other side to stretch out the process some, and that may be all the opening they need to stretch it out even more. It took over a year to get from nomination to confirmation on Sotomayor last time.
Still, the past history and developments since then look good. And having 59 Democratic votes to start with doesn't hurt, either. Though you never know where flaky votes like Ben Nelson's or Evan Bayh's are going to go. (Though I'd bet on Bayh staying home with the Dems on this one.)