What is the primary purpose of a political action committee?

The primary purpose of a political action committee is to financially support candidates who further their interests. political action committees allow a degree of anonymity to supporters to influence elections which large amounts of money so they are commonly used for this purpose. however, PACs also argue that they seek to increase awareness of a particular political issue in an election cycle as well. 

Walked would be the participle here. as it is a verb ending in -ed.