I don’t know who was next inline or had seniority for the Chairman of the Senate Judiciary Committee back in 2004.
Who was next should not be too hard to find out, but I doubt that senator would be as liberal as Specter, and if that senator was, he highly likely would have supported Alito or Roberts for SCOTUS.
The salient argument for the Santo defense is if he did not endorse Specter, he could lose, and/or if Toomey won the primary, he would not have won in the PA general election. And as a consequence, the Repubs would have lost the US Senate in 2004 because they had a thin margin of 51 Repubs v. 49 Dems. (It would have been 50 to 50 with VP Cheney as the tie breaker, Rs still in the majority, if the Specter senate seat was lost and the only difference)
But as it turned out, Bush won the 2004 presidential election, and the Republicans increased their Senate majority to 55 to 45. As we know, the Republican kept their majority even if Specter or Toomey would have lost in the general election. Rick is not all that shiny as some here like to think. He has his GOP-E rust spots who has set aside “his principles” for the party.
Here’s the 2004 Senate election results:
http://en.wikipedia.org/wiki/United_States_Senate_elections,_2004
There was also a grassroots campaign to stall Specter, which was talked about here on FR in 2004:
http://www.freerepublic.com/focus/f-news/1274088/posts
http://www.humanevents.com/article.php?id=5724
excerpt: "Pennsylvania Sen. Arlen Specter has failed to secure public support from members of the Judiciary Committee, and now even Pennsylvania’s junior senator, Rick Santorum, is officially "undecided" about supporting Specter's bid to chair the Judiciary Committee, according to a spokesman with the Senate Republican Conference, which Santorum leads."
Also, it seems a big claim by RS was Specter was shoe-in for the chairmanship, but that isn't necessarily true, as the rules are senators can vote for whomever they want, by secret ballot. Voting for the next person in line is a tradition and perk in the Senate, but not a hard and fast law.
So what seems to be emerging is a picture where, if Specter had lost to Toomey, things wouldn't have been so awful as predicted by Santorium; and after having endorsed specter, Santorium wouldn't even announce he was voting for him... Rick thinks his my hands are clean if you don't look between my fingers tack is going to win the day... that can't be allowed...