Former Rep. Pat Toomey (R-Pa.) has racked up another endorsement from one of his former House colleagues for his 2010 bid for Senate.“For as long as I have known Pat Toomey, he has been a reliable and steadfast supporter of limited government, lower taxes and personal freedom,— Rep. Bill Shuster (R-Pa.) said in a statement. Shuster is the third Pennsylvania House Republican to back Toomey, following endorsements from Reps. Joe Pitts and Charlie Dent. Pitts and Dent stayed neutral in Toomey’s 2004 bid, when he challenged Sen. Arlen Specter in the Republican primary. Specter has since switched parties and is seeking re-election next year as a Democrat.Shuster’s endorsement further solidifies Toomey’s status as the Republicans’ chosen candidate for the Senate race. When Specter announced in late April that he was running for re-election as a Democrat, several Congressional Republicans remarked that Toomey was too conservative to win a general election in the Keystone State. But as several other Republicans have ruled out running for the GOP nomination over the past two months, Toomey has inevitably become the frontrunner for the GOP nod. National Republican Senatorial Campaign Committee Chairman John Cornyn (Texas) has not officially endorsed Toomey but gave his campaign a $5,000 donation in June.