If you use ActiveCampaign.com for your campaign, from version 2.14.0 SpeakOut! can automatically add signers to your list of contacts if they check the “Add to mailing list” option, assuming you have it enabled and have ActiveCampaign enabled in the petition settings.
To enable ActiveCampaign go to dashboard > SpeakOut! > petitions > edit the petition > 3rd Party Extras tab. Checking the box will expose the fields that you need to find and enter.
API Key and server - https://mailchimp.com/help/about-api-keys/#Find_or_generate_your_API_key
Campaign ID - Open your campaign, look at the URL and find the ID number https://youraccount.activehosted.com/admin/main.php?action=campaign_new_list&id=1
Your new contact will be added to your account.
There are 2 likely scenarios that you may have. A single campaign with a number of petitions or a number of separate campaigns, each with its own petition.
In scenario 1, a single campaign, use the same ActiveCampaign API details for each petition.
If you have separate campaigns, assuming they are all in the same ActiveCampaign account, the only thing to change is the list ID for each petition. The API Key and server ID will be the same.
NOTE: for this to work, you must enable the ‘Display opt-in checkbox’ under the Display Options tab on the edit petition page. i.e. you can’t add people to your mailing list without their permission.