In theory, the switch made perfect sense. Arlen Specter would switch parties, have the primary field cleared for him, romp over Pat Toomey in the general election, then continue his Senate career as before. What could possibly go wrong?

Well, to start with, it increasingly looks as though Specter will have a serious primary opponent. While polling shows Specter is likely to win that matchup, it means he will (i) face the risk of losing, (ii) have to raise and spend money for the primary, and (iii) probably have to tack to the left to maintain his primary lead.

Then, speculation increased that former Republican Governor Tom Ridge would get into the race. The same polling linked to above shows Ridge thumping Pat Toomey in the primary, and then beating Specter in the general election (other polling shows the general election race quite close).

Now it appears that Harry Reid was unable to keep his promise to award Specter his seniority. According to CNN, a resolution today prevented Specter from retaining his seniority. This is a double blow for Specter. First, he can no longer argue to Pennsylvanians that his seniority is a benefit to the state.  This makes problem one and two above harder to overcome, as he loses one of the major arguments for his candidacy.  Second, Specter does not strike me as a man with a small ego, yet he has dropped from being the twelfth most senior senator to coming in right below Kirsten Gillibrand, who was in diapers when Specter was starting his political career. I would imagine that isn't easy to take. To make matters worse, there isn't much he can do about it; what can he do, switch parties back?

So far, Specter's best day as a Democrat was his first day.

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