Each State gets a vote for each Congressman and Senator in the electoral college. The smaller States thus have an elector for each 200,000 to 300,000 plus population, while the larger states have one elector for each 600,000 to 700,000 people. This advantage comes from a compromise in 1787.
It is unfair to large cities and urban states, but almost impossible to change. The smaller states would never agree to lessen their advantage.
Since 1787 we have substantially changed our voting rights. We let unpropertied men vote, then African Americans, then women. It would be interesting to see if a well-reasoned lawsuit could change the current situation.