CiviCRM is an open source constituent relationship management solution for the civic [non-profits, charities, political parties, unions, associations] sector.

CiviCRM describes itself like this:

CiviCRM is an open source and freely downloadable constituent relationship management solution. CiviCRM is web-based, open source, internationalized, and designed specifically to meet the needs of advocacy, non-profit and non-governmental groups. Integration with both Drupal and Joomla! content management systems gives you the tools to connect, communicate and activate your supporters and constituents.

I have been working with CiviCRM since 2005, see a list of CiviCRM projects I have worked on.

I strongly recommend CiviCRM to many of my clients and am happy to talk to you about whether it might be a good solution to your needs. I also host the domain "civicrm.ca".