We can expect higher than normal voter turnout for the special election given that presidential elections tend to boost voter turnout. (michaelbenjamin2012.com)
A system where normal voters and not just a dedicated few get to pick the candidates for the major parties who will duke it out at the election. (politics.co.uk)
In fairness, I should probably add that in a fair number of cases, Democrats (both politicians and just normal voters) might well take similar positions in any case. (politics.stackexchange.com)