Liberal democracy requires the availability of liquid capital (and therefore capitalism), because with only illiquid types of capital (land, social ties etc), there is no freedom and mobility. Other types of democracy may not require it, but they are not used much currently.
Correct, it is named for accumulation of capital. However I don't know of any systems that are liberal (which is a nice feature) and democratic, without being also capitalistic. Maybe there some theoretical ones.
