We're in a state (Minnesota) with no party registration. After reviewing the data that came in from Election Center, it looks like the "inferred_party" field for all records is either a "U" (Undeclared) or an "H".
We looked at the article that's supposed to describe the values for this field (http://nationbuilder.com/support_for_international_parties), but didn't see an "H" in the list of valid values for the U.S. It doesn't seem to map to any of the values defined for our database (Democrat, Republican, Green, etc.), because I can see the H value when I export the records, but I never find any of those records when I perform an Advanced Search with any of the valid values in the Inferred Party drop-down list.
Does the "H" have some meaning?
Want to let you know that the Election Center team is currently investigating the data and shape files associated with your data request. They'll be in touch as soon as they finished lookin' in to the issue.