A petition is a request for doing something which is commonly addressed to a government officials and public entities. In the colloquial sense, a petition is a simple document signed by numerous individuals and addressed to some selected officials. This article lists some useful plugins you can use to add petitions forms and signatories in your WordPress site.
SpeakUp! Email Petitions
Using Speak Up! Email Petitions plugin you can easily add petitions to your WordPress site and rally your community for support a cause. You can create your own petition forms with in your website (view screenshots).
YAWPP (Yet Another WordPress Petition Plugin)
The plugin allows you to add petitions forms and signatories to your WordPress site posts and pages. You can Create new petitions, Choose the maximum signatories you wish to display, Add some fields to your petition, See the list of petitions created, See the list of signatories for each petition, Enable/Disable each petition, Delete each petition, Delete each signatory etc
ecampaign
Another WordPress petition plain that allows a simple petition or email campaign action to be embedded into a post or page. Your website visitors can get automatically registered as users, details can exported to CSV file and there are many many more features.
We The People
In May 2013 the White House released API for We The People, a petition application designed for the citizens to provide them a direct line to the White House. Anyways, this is the most unpopular WordPress petition plugin that allows you to embed White House petitions from We The People into your WordPress site via shortcodes and widgets.