We never had sixty Senators. We had about 45 Dems, a dozen or so Conservadems, Arlen Specter, who only joined the Dems to avoid losing a GOP primary challenge, a temporary replacement for Kennedy, and Joe “I oppose legislation I supported last week because I found out liberals liked it” Lieberman.
On rare occasions, when the sun was shining, the birds were signing, all the moons and planets were in alignment, and absolutely everything that could possibly go wrong didn’t, this mass of conflicting interests could be brought together to form a block that was technically sixty votes. Now that’s gone. Big deal.