In most liberal democracies, political parties often adopt different positions on many issues and thereby provide voters with a choice on a variety of matters. However, in standard voting models, it is assumed that political parties strive to converge on the median position. Therefore, one could argue that the existence of different political parties makes little difference. This is because regardless of the initial political stance of the winning candidate or party, in most cases they will identify the same electoral issues and often adopt similar measures in response.
However, in reality certain factors prevent parties from fully converging on the median voter position. While, candidates themselves might be unable to appeal to the median voter position due to strong personal beliefs or principles, the internal structure of parties also may play a part.
Most often, political parties with internal democratic mechanisms will elect party leaders who can appeal to most median voters but whose ideology and policy principles are closer to the party's position than the rest of the electorate. For example, a left-wing party will be keen to elect candidate who can appeal to median voters but would be more left wing than the rest of the electorate. In this case, the candidate might occupy the median position within the party, which would still be more left wing than the rest of the electorate.
In response to recurring problems and issues, modern political parties embarked on wide reforms aimed at creating more transparent and democratic mechanisms. In the US, many states feature primary elections and party caucuses that are better regulated. Therefore, most often, the winning candidate of the democratic or republican nomination emerges quite clearly and early in the process.
As a result, party conventions ceased to be events in which parties choose candidates and became more of a formality in which the nomination of a candidate was officially announced and celebrated. In the UK, the Labour party began to choose its party leader through an electoral college, which was composed of a third of each of the votes of party legislators, members associated with the trade unions and individual party members.
These changes were certainly welcomed, as they seemed to address many of the flaws of the existing systems through more democratic and transparent mechanisms. The new election processes not only opened up the leadership process of political parties but also made it more accountable. However, critics argue that these reforms have exposed modern political parties to a new set of problems.
One of the major criticisms is that modern political parties no longer fulfill the role of being independent organizations that feature their own unique character and the ability to bring together contrasting social interests to the political process. Furthermore, the reforms have transformed the election of party leadership into a spectacle that is comparable to a general election. This has allowed other forces such as the media, interest groups and business co-operations to play a more significant role in the internal election process of a political party. The expanding influence of these forces has come at the cost of the influence held by traditional party groupings. Thus, the ability of political parties to develop policy ideas and allow leadership candidates to emerge has declined significantly.
In the early 20th century, it was vital for political parties to develop a network that could rapidly recruit members, supporters and election workers from amongst the voters. Thus, parties were massive organizations that could mobilize thousands of election workers during the election cycle. Failure to organize on a large-scale often meant loosing the election. However, by the 1970's parties began to evolve into a 'catch all' model. This required party leaders to run a more direct campaign and winning candidates had to successfully appeal to the electorate and the media.
As a result, political finance became extremely valuable in order to finance media coverage, opinion polls, focus groups and other elements of a political campaign. This change transformed political parties into more flexible organizations that could quickly evolve around a new leadership and the significance of the party bureaucracy declined. More importantly, these transformations also coincided with the dwindling levels of party membership.
Just as campaign financing became the most important resource in any election, major political parties began losing their key sources of revenue such as party subscription fees and individual donations. Thus, party leaders had to depend on large donors in order to gain the necessary funds for election campaigns that have become increasingly more expensive. This dependence has exposed political parties to significant amount of influence from wealthy individuals and corporate donors.
Therefore, powerful donors can set the agenda of an entire political campaign or fund candidates who champion policies that are favorable to their interests. This has even caused some critics to argue that party leaders are now becoming more focused on designing policies in order to attract wealthy entities.
As a result, voters are tasked with electing representatives who are more inclined to serve the interests of their major donors rather than their constituents. This has arguably set about a vicious cycle in which the influence of powerful donors discourages ordinary voters from taking part in political parties or making significant donations because they feel that their influence will always be very little in comparison, which in turn forces party leaders to depend on such donors even more. The wide range of campaign-finance related scandals that have plagued elections in liberal democracies in the past few decades have not helped to improve things either.