A concerted Russian hacking and online disinformation campaign helped tip the 2016 US presidential election toward Donald Trump. Two weeks ahead of midterm congressional elections, Moscow's operatives are at it again.

The shutdown of thousands of Russian-controlled accounts by Twitter and Facebook -- plus the indictments of 14 people from Russia's notorious troll farm the Internet Research Agency -- have dulled but by no means halted their efforts to influence US politics.

#MAGA -- Trump's rallying call to "Make America Great Again" -- remains the top hashtag among 18,000 tweets pumped out daily by hundreds of Russia-backed and allied Twitter accounts monitored by Hamilton 68, a tracking operation of the Alliance for Securing Democracy in Washington.