On the surface, it would seem that the House of Representatives is more democratically elected than is the Senate, since the number of House members is proportional to population, whereas Senate members are not. However, it is not that simple.
The Senate members are voted on by all of the states electorate, whereas House members are each voted on only by a single district. And this is where serious abuses occur. Except for California, which has a neutral commission to draw district lines. Gerrymandering is widespread, especially in the south and Midwest. To make the House of Representatives honestly represent voters it would be necessary to outlaw gerrymandering and to follow Californias example of having, in each state, an unbiased commission to draw district lines.