Tom filled this last slot. He was dem senate minority leader until he lost in 2004. He knew all the repubs and dems AND was well liked. (Being liked is critical because of the country club atmosphere that is the senate.)
When he withdrew his nomination, he set back the healthcare movement months maybe years. It will take some more time to find a successor and more time for the successor to establish him/herself. This was all preestablished with Tom.
While it is bullshit to screw with the government out of hundreds of thousands of dollars, I still overlook that for the greater cause, national healthcare