Obama was introduced and endorsed by Senator Bob Casey , Jr. , who had indicated earlier that he would remain neutral in the democratic primary .
On March 28 , Obama started the bus tour with a rally in Pittsburgh 's Soldiers and Sailors Memorial Hall .
Obama was introduced and endorsed by Senator Bob Casey , Jr. , who had indicated earlier that Obama would remain neutral in the democratic primary .
On March 28 , Obama started the bus tour with a rally in Pittsburgh 's Soldiers and Sailors Memorial Hall .