Very. Expensive, and many states have legal restrictions on what you can use it for and who can get it.<p>Nationbuilder, a sorta-competitor to NGP, has put together a national voter file and it&#x27;s reasonably priced. 
<a href="https:&#x2F;&#x2F;elections.nationbuilder.com&#x2F;about&#x2F;faq" rel="nofollow">https:&#x2F;&#x2F;elections.nationbuilder.com&#x2F;about&#x2F;faq</a><p>The DNC&#x2F;NGP voter file, however, is significantly enhanced - for one, it&#x27;s got a lot of phone numbers, which most states don&#x27;t include in their lists. There&#x27;s a lot of other survey and consumer data associated.<p>For a national voter file that&#x27;s good enough to use for say a City Council race anywhere in the country, where all you want to know is &quot;who is likely to vote in this non-presidential election&quot;, it&#x27;s doable but very expensive. For anything serious, it&#x27;s pretty much outside of capabilities of anyone but the parties and some of the very big SuperPACs&#x2F;very big orgs.