(from the article `primary election`) ...party members to vote, or open (nonpartisan), enabling all voters to choose which party`s primary they wish to vote in without declaring any party ... Found on http://www.britannica.com/eb/a-z/d/53
Direct primary (Political Science) A primary by which direct nominations of candidates for office are made. Found on http://www.encyclo.co.uk/webster/D/72