Single ballot theory

Arlen Specter looks to be in trouble. From 'Poll: Toomey narrows Spector's lead':

A surge in support for conservative challenger Rep. Pat Toomey has narrowed Sen. Arlen Specter's lead to a scant 5 percentage points a week before Pennsylvania's Republican primary, according to a poll released Tuesday. Toomey, a three-term congressman from the Allentown area, was backed by 44 percent of likely Republican voters, compared with 49 percent for Specter in the survey by the Quinnipiac University Polling Institute. Seven percent were undecided...

President Bush has endorsed Specter and appeared at a Specter fund raiser in Pittsburgh on Monday night. But national conservatives have funneled nearly $2 million worth of contributions and attack ads into the state to help Toomey, who has also spent another $2 million since the start of the year...

Let's hope Toomey pulls ahead. See, for instance, 'The Awful Specter of Yet Another Term'. See also his voting record on immigration.