At the Constitutional Convention, states naturally argued for representation of their own state. Large states wanted representation that was proportional to their population. Edmund Randolph proposed James Madison's Virginia Plan which called for a two-house legislature. The number of delegates each state had in the lower house would be proportional to that state's population, and members of the upper house would be elected by the lower house (therefore all of it was mainly dominated by state population).
Of course the smaller states with less population objected to this plan. William Paterson proposed the New Jersey Plan in response, which had a single house legislature where every state would have equal representation in it.
