The poll by the respected Levada Center gives Medvedev an approval rating of 76 percent, just below Putin's rating of 77 percent. This is the closest the two of them have been in the monthly survey, though for much of this year their ratings have fallen within the margin of error of plus or minus 3.4 percentage points.
Although technically now Russia's No. 2, Putin is still seen as the more powerful leader more than two years after handing over the presidency. The prime minister is eligible to return to the presidency in 2012, and he and Medvedev have said they will decide between themselves which one of them will run.
The newspaper Vedomosti on Friday cited Levada Center sociologist Alexei Grazhdankin as saying that the rise in Medvedev's approval rating may reflect the popularity of some of his recent actions, including his firing of the Moscow mayor and efforts to reform the police.
But Grazhdankin cautioned that it was too early to say that polls for Medvedev and Putin had now evened out.
He said if the country remained relatively stable, Russians would be content with Medvedev, who has made modernization his main focus. But if Russia were hit with another wave of terror attacks or armed conflict, people would look to Putin, who is seen as a strong defender of the Russian state.
The poll of 1,600 Russians, conducted Oct. 22-25, was released Thursday.