The presidential campaign is gearing up in the US, and opinion pages and social media posts are full of passionate declarations of support and/or disapproval of a specific candidate. Most of these are not going to convince people to change their mind though.  In most cases, the audience and the "presenter" probably agree already, they read the same newspaper, watch the same channel and are friends connected on social media.  

To make change, you need to convince the people that are doubters, the people in the centre. You don't do that by implying that supporters of the other side are not very smart or insulting them in other ways.

Think about the doubters, what it the final straw that might convince them to switch sides?

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