However, results Thursday released by the independent Levada Center indicated that if the election were held this weekend, Putin would win 42 percent of the vote, not enough to win in the first round of voting, The New York Times reported.
In a statement, VTsIOM said Putin retained his "solid lead" in the race, picking up 6 percentage points from 42 percent to 48 percent during the past few weeks.
The state-run agency said support for other candidates has been stable -- 10 percent for Gennady Zyuganov, 9 percent for Vladimir Zhirinovsky, 5 percent for Sergei Mironov, 3 percent for Mikhail Prokhorov and 2 percent for Grigory Yavlinsky.
Putin's campaign found itself answering questions about why not all of the posts to his online suggestion box were published after an online blogger found a way to access the submitted-but-not-posted comments, the Times said.
Putin's campaign said the site's moderators removed only suggestions that contained obscene language and that the site seized up because so many suggestions were submitted.
The Times said several suggestions that Putin resign were published but later removed.
"Please leave politics; it is obvious that power is a narcotic, but it is the right thing to do," one posted-then-removed comment read.
Putin's campaign said he wouldn't engage in presidential debates because he was busy carrying out his duties as prime minister, the Times reported.
Zyuganov, Communist Party presidential candidate, wondered on the party's Web site why debates are part of the process elsewhere but "here the 'party of power' has calmly walked away from open debate for 15 years."