republican u.s. senator lindsay graham testify thursday character witness behalf democratic colleague bob menendez trial federal corruption charge newark new jersey graham testify six minutes tell jurors know new jersey senator honest trustworthy man accord twitter post reporter star-ledger newspaper courtroom democrat cory booker new jersey junior senator also expect testify character witness booker former mayor newark previously attend trial support menendez statement graham office say testimony would service menendez charge graham represent south carolina travel expense statement say menendez enter courthouse thursday tell reporters honor graham booker would testify menendez 63 accuse take bribe wealthy benefactor florida ophthalmologist salomon melgen exchange use office help melgen menendez melgen deny wrongdoing say relationship simply close friendship prosecutors say menendez intervene melgen behalf medicare officials agency conclude doctor overbilled millions dollars melgen convict separately early year massive medicare fraud menendez also accuse pressure federal officials secure visa melgen girlfriends resolve port dispute involve one melgen businesses exchange menendez aid melgen give senator private flight luxury vacation hundreds thousands dollars campaign money prosecutors say case closely watch washington republicans hold 52-48 edge senate menendez convict either resign expel republican new jersey governor chris christie term expire january christie would name replacement top republican senator testify menendez bribery trial