As of 6:00 p.m. Moscow time (3:00 p.m. GMT) on Sunday, the figure had already overtaken the 56% voter turnout in the 2003 elections to the State Duma, the Central Election Committee said.
Preliminary voting results and exit polls are set to be announced at 9:00 p.m. Moscow time (6:00 p.m. GMT), soon after the last polling stations close in the westernmost part of Russia, the Baltic exclave of Kaliningrad.
Russia is holding the fifth parliamentary polls of its post-Soviet history. The election is expected to cement the pro-Kremlin United Russia party's position for the next four years.
The only other parties expected to overcome the 7% threshold required to enter parliament are the Communist Party, the ultranationalist Liberal Democratic Party, and A Just Russia, led by Kremlin loyalists.
President Vladimir Putin decision to top United Russia's party list has given the bloc a major boost. The president, who has overseen eight years of rapid economic growth and the reemergence of Russia as a key player on the world stage, retains high popularity ratings among the core electorate.
