Senators are elected by a straight majority of that state's votership. Which means that both California and Wyoming get 2 senators despite the huge population difference.
Oh and smalls states are hugely overrepresented in the House too. Each CA rep has, on average, 465,674 constituents (TX-167,637; NY-129,187 ). For New Hampshire it's 3,291 and for Wyoming it's 9,394.
That means small states' voters have orders of magnitude more power than large states' in all phases of federal elections. It's horseshit. If small states had the advantage in just the electoral college I wouldn't mind, but the "tyranny of the majority" argument only goes so far.
Sens and Reps are reflective of their states/districts needs, but some states/districts are wayyyy overpowered on the national level.