Eye on 2010 reported last month on the regularity with which Pennsylvania Sen. Arlen Specter voted with Democratic leaders since he left the Republican Party in late April.

The Senate has cast a lot more votes in the past month, and Specter, who faces a serious challenge from his left flank in the Democratic primary, has been even more of a party loyalist.

Since Specter’s party switch was noted in the Senate voting rolls on April 30, he’s participated in 63 votes that have essentially divided the two parties and sided with the majority Democratic position on 57 of them, for a CQ-defined “party unity” score of 90.5 percent. Since the July Fourth recess, Specter sided with the consensus Democratic position on 40 of 43 party unity votes in which he participated, or 93 percent of the time.