A political party refers to a formal or informal organisation with an internal structure, which aims to change the society they operate in with certain policies. They generally publish a chart or party programme, and take in members who feel they find themselves in what the party proposes. This is true of both bourgeois and proletarian parties, though the strategies differ.
Political parties are not limited to the "pure" political sphere (elections, parliaments, etc.). Their policies have effects on people and will change the general landscape of the country they pass those reforms in for years to come.
They can also be informal, for example when communist parties are banned (as was the case in France, the USA, Ukraine, Australia, Switzerland and countless others).
In liberal republics, or more generally in capitalist bourgeois societies (as they can be something other than republics), parties rely solely on electoralism to achieve their goals. They hope that by controlling the assembly (a parliament who wields legislative power) they will be able to reform capitalism as they see fit. Though capitalism can only be reformed to capitalism and will remain bourgeois (as the state is bourgeois). If there are, say, 100 seats in parliament and a single party controls 51 of those, they can essentially push through any law they want provided it needs only 50% of the votes plus 1.
Their internal structure is usually reliant on a cadre of well-connected people at the top (who run for elections, as they have the best chance of winning as individuals), and then mostly members who pay huge membership fees each year towards the party, but otherwise don't care to participate -- as there are usually not many projects they can participate in, since they are not elected and efforts are focused on electoral things (passing policy in parliament, preventing policy from passing, organising elections and campaigns...). Most bourgeois parties, for example, hire people specifically to gather signatures for referendums (policy is directly submitted to the popular vote) or petitions instead of asking for volunteers from their party base. Thus the party base is alienated from the leadership and has no say on their decisions.
Therefore in liberal republics, major parties usually exchange power between each other year after year and nothing really happens, things stagnate as a project spearheaded by the party in power will be overturned by the next, more reactionary or progressive party that gets elected. Minor parties are almost entirely pushed out of the political process as they cannot compete in parliament. They will often form alliances with similar parties.
Proletarian (and revolutionary) parties in liberal republics have an entirely different character. As Lenin explained in Left-wing communism: an infantile disorder, proletarian parties should only participate in bourgeois elections for two reasons:
- to gauge the popularity of the revolutionary party and let the bourgeoisie know it exists.
- to expose bourgeois elections for what they are: an idealist notion, an oppressive structure that will never allow actual dissent.
Otherwise, the role of the revolutionary party is to guide the people towards the socialist revolution. This takes place through actively mobilising people, so as to remove their alienation towards the political process and get them to fight for their rights. The vanguard party will thus be formed, and will be the party which best achieves their goals. Whoever is best at mobilising the masses to respond to their material needs and fight for socialism is by definition the vanguard.
Likewise, the structure of the revolutionary party is usually different from bourgeois parties. They usually follow democratic centralism. The party base (the membership) is incited to participate both "on the field" (projects) as well as internally (self-criticism as well as criticism of mistakes the leadership has made). It will usually be reinforced that once a decision is taken by the party, all members follow it even if they do not agree with it -- criticism is encouraged, but the party must be able to take action quickly when needed.
The projects of the proletarian revolutionary party range from direct action to policy-making when applicable. The proletarian party will participate in or organise protests, strikes, etc.
Therefore the goal of the proletarian party is not to reform capitalism into socialism from within, but to replace the system entirely and install socialism in its place.
In socialist republics, we generally see the rule of the revolutionary party safeguarded in their constitution. In such cases, there is a leading party which cannot be removed from power, but other parties are usually allowed provided they are not reactionary, and only as auditors and councillors (meaning they can advise police but cannot directly change it). The structure of the revolutionary party is entirely different at this stage from what it would be in a liberal republic; since the party is in power and has the authority to pass legislation, they inherently take on a different role. In the socialist republic, the party makes sure that reactionary groups are not allowed to prosper, because it would mean the end of the revolution. Their second main task is to build productive forces in a way that will make the people prosper, so as to reach socialism -- a state where there is no exploitation of labour, the proletariat is in power, and eventually all class distinctions will cease to exist in communism.
Government positions are not necessarily held by the party, in many cases (such as in Cuba) anyone is allowed to run for elections, and being a member of the party does not have any bearing on one's election process.
Members of the party in fact are usually submitted to tests to filter out opportunists or careerists (people who want to become career politicians to gather power and wealth) -- membership is not as easy as paying a yearly fee. Members are also expected to participate in the party, and usually carry either formal or informal responsibilities in their communities.
In this case then, the role of the revolutionary party is to guide the country towards socialism and then communism without falling to reaction, which would spell the end of the revolution.
- Pat Sloan, 1937, Soviet Democracy.
- V. I. Lenin, Left-wing communism: an infantile disorder, ch. 7: https://www.marxists.org/archive/lenin/works/1920/lwc/ch07.htm