Difficult to lead
Three main parts are: the party in the electorate, the party as an organization, and the party in government

-Serve as linkage institutions that translate inputs from public into outputs from policymakers
-Pick/nominate candidates
-Run campaigns
-Give cues to voters (party affiliation)
-Articulate policies
-Coordinate policymaking

Parties and political actors have pragmatic goals (such as winning elections) that are more important to the party than ideology

Not much difference between them; but given nature of political market they have little choice.