Moscow ? Russian lawmakers moved to lengthen the presidential term from four to six years on Friday with a vote that opponents called a step toward Vladimir Putin’s return to power.

The change means that the powerful prime minister could serve a total of 20 years as president if he returns to the position as many expect.

The office of Russian president “already has more power than the General Secretary (of the U.S.S.R.), the czar and the pharaoh together,” Communist Party leader Gennady Zyuganov complained shortly before the State Duma voted 388-58 to approve the constitutional amendment. It faces two more votes in the Duma, or lower house of parliament, and appears certain to be enacted.

Political analysts and Kremlin foes predict that President Dmitry Medvedev could step down as early as next year, making his former patron acting president and triggering elections in which Putin would run and likely win.