With the final defeat of Jim Martin in Georgia, it's now certain that the Democrats will not hold 60 seats in the Senate and may have to settle for 58 (I'm growing skeptical of Al Franken's chances).
A point which I think is obvious, but which seems lost on the nattering nabobs who form public opinion is that there is no meaningful or practical difference between having 58 seats or 60 seats. There are just too many variables inside the Democratic and Republican caucus to prevent either group from voting in perfect lock step with their respective party leadership.
In the Democratic caucus there are conservative senators and liberal senators who represent very different constituents but have the common interest of being re-elected. It's naive to believe they will both always vote together on legislation sponsored by the Obama WH or Harry Reid.
Ben Nelson (D-NE), Mary Landrieu (D-LA) and Mark Pryor (D-AR) are among the most Conservative Democrats in the Senate and all hail from McCain states. It should go without saying that they will view many issues very differently than Dick Durbin (D-IL), Patrick Leahy (D-VT) and Barbra Boxer (D-CA) who are among the most liberal Democrats (by voting record) from the bluest of states.
And these same factors apply to several Republican senators who come from very blue states including Olymbia Snowe (R-ME), Susan Collins (R-ME), and Arlen Spector (R-PA) who is up for re-election in 2010. Other senators from Blue states up for re-election in 2010 include Chuck Grassley (R-IA), Judd Gregg (R-NH), Richard Burr (R-NC), and George Voinovich (R-OH). While many of these are considered safe seats, their consitutents who voted Obama do not expect them to be filibustering the new president's agenda.
So when you actually get down to counting votes, there isn't anything magic about having 60 Democratic Senators. Get 65 Dems and you can start feeling like you have a supermajority.