Organic reach via social media is limited
There is another route to reach voters through the use of social media. Messages can be posted via a party's own account that are intended to get voters' attention. Such an approach is in fact the average use of these media and it is free. But even if you fax lists have many followers, the data companies use algorithms that determine which message reaches whom. As a result, parties do not reach all followers. A party has no influence on that. And the reach via this route is often quite limited. Such a message then only reaches people who were already consciously following that party.
Trump has already proven that the cunning use of a medium like Twitter can create a bubble among his loyal followers. It can deafen them to other voices.
In short, the use of digital media can yield surprising results. It will mainly depend on who knows how to use these media optimally.
How do we reach all voters, without selectivity and manipulation?