Russian MPs are to vote on a Kremlin-backed law which would impose harsh regulations on all of Russia's foreign-funded non-governmental organisations involved in political activity.
The bill is expected to win preliminary approval today in the Russian parliament.
It is all part of a broad crackdown on civil liberties and dissent that has accompanied Vladimir Putin's return to the presidency in May.
Grigory Melkonyants, deputy director of Golos, a group that compiled evidence of thousands of electoral violations in Russia's recent elections, says authorities would now have "a hundred different ways to render us ineffective".
The pro-democracy group depends on grants from European nations and the United States. Golos would have to declare itself a "foreign agent," a term that is still synonymous with espionage for Russians who lived through the Cold War.
The Kremlin-backed United Russia party, which has a majority in parliament, is expediting the bill and it could come up for a final vote as early as next week.
Golos has faced growing pressure since November, when Putin accused Western governments of trying to influence the December parliamentary election by funding Russian NGOs. A Kremlin-friendly national television station then aired a programme that attacked Golos directly, showing shots of suitcases full of US dollars and claiming that Golos was openly supporting opposition parties.
Golos then became the focus of police raids, detentions and cyber attacks.
Still, the organisation was able to field thousands of observers in December and again in March for the presidential election that gave Putin a third term. Golos also ran a website that compiled evidence of thousands of electoral violations nationwide.
Under the new law, any material such groups distributed would have to come with a warning that it was written by a foreign agent, and organisations would have to file detailed quarterly financial reports. Failure to comply would bring fines and eventually jail sentences.