In August, news stories from Florida Senator Bill Nelson indicated that likely-Russian operators had compromised parts of Florida's election systems ahead of Novembers election .
Ongoing Campaigns
The nature of election interference and the clear affect it can have on national security means that particular details of ongoing campaigns remain difficult to identify. Government officials are reluctant to reveal too much information on ongoing investigations, whilst social networking sites such as Facebook and Twitter appear to ban accounts as and when they are identified on the platforms. The Bloomberg article referenced above includes claims that the operators of allegedly fake pages adapted their approach to advertising, paying in US and Canadian dollars instead of Roubles for example.
Whilst it seems any involvement of the Russian state in previous campaigns was much more about influencing the electorate to vote a specific way, the breach in Florida suggests that tampering of results or attempting to adjust figures could be a potential target for anyone who would wish to interfere with the democratic process.
An allegedly leaked report from the NSA identified there was a GRU Campaign Targeting US Local Election Officials between August and November 2016. The vector for attack was through third-party providers rather than the election officials themselves, and focused on voter registration. The report unfortunately does not identify the intention of the attack or the level of success of the attackers. It is however possible similar activity is currently ongoing.
Away from the Russian-based threat (or indeed, perceived threat), FireEye identified in July a Compromise of Cambodia's National Election Commission , Fusion Center covered this story in the report Leviathan Targets Cambodia Ahead of July 2018 Elections . This incident itself showing that the threat to election campaigns doesn't necessarily have to originate from Russia, and that it's likely a number of nations are performing similar activity.
Another potential avenue that may be exploited and saw attention in 2016 is the use of non-mainstream media. Sites like Breitbart and Politico were allegedly used by Russian operatives to spread messages to encourage people to support the Trump campaign and denounce his opponent Hilary Clinton, and since election these types of sites have received more attention (including conspiracy-site InfoWars). Whilst these sites are not 'mass-media', similar to social sites such as Facebook and Twitter, the echo chamber effect of repeatedly spreading messages to the same audience can work to change perceptions over time. At time of writing Fusion Center analysts were not able to identify sockpuppet accounts looking to spread these kinds of messages, however investigations are ongoing.