This chapter considers some of the implications of these developments with respect to the democratic process. It investigates whether the decline in challenger quality has helped to insulate incumbents from electoral vulnerability. Some scholars believe incumbency advantage may threaten the fundamental character of representative democracy in America. Incumbency advantage appears to have stopped growing in US elections because both its direct and indirect components have stopped growing. Growth in the incumbency advantage that emerged in the 1960s has been explained by emphasizing incumbent resources, including opportunities to perform constituency service, partisan dealignment, fundraising advantages, strategic entry, redistricting, party machine structure and the spread of local television news. Gary W. Cox and Jonathan N. Katz concluded that growth in incumbency advantage was fueled by the increase in the quality effect. They suggest the increase in the quality effect was driven by a decline in partisanship within the electorate that heightened the importance of candidate quality as a voting cue.