The representative democracy realizes the sovereignty of the people through the election of a representative. Specially the political parties are going to accomplish their platform with a law and a nation policies by the winning their standard-bearers nominating to the public official election in the political party democracy. Korean major political parties are enforced the direct primary election system in the process of intraparty competing nomination. Korean major political parties permit unaffiliated electorates to vote in the nomination of candidates and they make use of surveys of public opinions of the candidates in high proportion in evaluation. It casts serious doubts whether distortes the party`s ideology and representation or not. The concern about party nonmembers selecting party nominees addresses the problems of crossing over and raiding. Party raiding describes a tactic in American politics where members of one party vote in another party`s primary election in an effort to either nominate a weaker candidate or prolong divided support between two or more contenders for that party`s nomination (especially for president). The Jones district court addressed whether blanket primaries violated the freedom to associate in practice. The court rejected the parties` arguments that the blanket primary severely burdens parties` First Amendment association right merely because it encourages crossover voting, a phenomenon where a person not associated with a party votes in that party`s primary. It explained that blanket primary laws are not severe because blanket primaries do not increase the prevalence of party raiding, the most egregious type of crossover voting. In reaching this conclusion, the court distinguished between three different motivations behind crossover voting: sincerity, strategy, and raiding. In assessing the threat of party raiding, the court was persuaded by the "almost unanimity" among experts, who agree that party raiding is not a realistic threat under blanket primaries. Unlike the district court, the Supreme Court found that the blanket primary law must withstand strict scrutiny because it characterized the burden on parties` association right as severe. But, these analysis of Party Raiding are the results. "First, True Raiding is unlikely. Second, Raiding is theoretically possible in all primary systems. Third, Raiding is a party problem, not a government problem." (Deidra A. Foster, 29 SEAULR 449, at 478-480) Also, according to the empirical analysis, no evidence of organized Raiding appeared in any election. That is to say, the bad influence of Party Raiding is modest to nonexistent. The Court in Jones proposes a "Nonpartisan" Primary. The Court concluded that a nonpartisan primary would serve the state`s interests without imposing severe burdens on political parties` freedom of association right. According to the analysis the Jones Court`s proposed nonpartisan primary or the Louisiana blanket primary, one will find that the systems are unconstitutional. Therefore I propose the open primary system based on the classifi- cation between party membership and party affiliation.