Two other candidates TG Venkatesh and V Vijaysai Reddy have also been elected unopposed in the biennial election to the Council of States.
Election Returning Officer and AP Legislature Secretary (in charge) K Satyanarayana Rao formally declared the four nominees elected unopposed as the process for withdrawal ended at 3 pm on Friday.
V Sunanda Reddy, who filed nomination as a dummy candidate on behalf of the YSR Congress, withdrew her papers on Thursday, paving the way for the unanimous election of the four main candidates.
Prabhu is a BJP nominee supported by the ruling Telugu Desam Party (TDP).
Chowdary and Venkatesh are TDP candidates, while Vijaysai is the lone opposition YSRC nominee.