All elections, or just elections in liberal democracies? I can't think of any major Marxist country that didn't do some form of representational democracy, even if the elections are just a formality. China does it. The Soviet Union did it. They didn't make elections dissappear, they just kept politicians that disagreed with the party line from running.

In large societies, not every decision can be made through direct democracy, so we need someone to make those decisions. Why not have a legislature? Is a group of unelected decision makers better?