http://efa.iykpqm7jiradoeezzkhj7c4b33g4hbgfwelht2evxxeicbpjy44c7ead.onion/toolkits/building-coalitions
However, if someone routinely sends controversial and off-topic posts, approach them off-list and politely request that they stop. You want to encourage productive on-topic exchanges and long-term relationships. Send emails to the list regularly with links to relevant news articles and updates on the campaign.