Liberals face campaign inquiry

Prosecutors announced a forgery investigation of the campaign of the only liberal Kremlin critic still in Russia’s presidential race, which is expected to be won easily by Dmitry Medvedev, Vladimir V. Putin’s handpicked candidate to succeed him.

Liberal opposition groups are weak, and former Prime Minister Mikhail M. Kasyanov is believed to have no chance, even if the investigation doesn’t push him out of the race.

A spokeswoman for the prosecutor-general’s office said the inquiry involved possible forged signatures on nominating petitions. She said the signatures were found in the Yaroslavl and Mari El regions.