"Information received up to 3 pm from the election monitoring system says polling percentage is 51 percent," an election official told IANS.
Polling has remained peaceful so far, he said.
Over 15 million voters will decide the fate of 98 candidates contesting the 11 Lok Sabha seats and 747 candidates vying for the 77 assembly seats.
Prominent among the Lok Sabha candidates are Congress stalwart and union minister Srikant Jena, ruling Biju Janata Dal's industrialist-turned politician Baijayant Jay Panda, editors of two leading local dailies, BJD's Tathagata Satpathy and Bhatruhari Mahtab.
All are members of the outgoing Lok Sabha and are seeking re-election.
Prominent among candidates seeking re-election to the state assembly are eight ministers of the state government.
They are Damodar Rout, Devi Prashad Mishra, Maheswar Mohanty, Pratap Keshari Deb, Badri Narayan Patra, Bijoyshree Routray, Rajanikant Singh and Arun Sahu.
Re-polling is also being held in 22 polling stations where voting was disrupted in the first phase April 10.