Does liberalism undermine or promote democracy?

Socialism can promote democracy, but it ultimately depends on the type of socialism we are talking about.

Traditionally, socialism promoted economic democracy, which means equal power relations and collective-decision making in the workplace. This may have taken the form of direct democracy on the part of each worker, or it might have meant democratically electing management.

This type of democracy is still promoted by modern day market socialists and advocates of decentralized planned economies.

If we are talking about the type of socialism that existed in the Soviet Union and "Communist states", then many political scientists would say no, this type of socialism did not promote democracy. The Soviet Union had a command economy, where decisions were made in a hierarchical chain-of-command.

Ironically, the Soviet model of "socialism" was inspired by capitalist management practices known as Taylorism and scientific management.