[aristeides]

Actually, before the 17th Amendment, a number of states had laws that their legislatures would select the person who had won a popular election for the Senate seat in question. This was a "reform" of the Progressives that was gradually winning sway in more and more states. The 17th Amendment made popular election mandatory for all the states.

[Cboldt]

I didn't know that. Very interesting tidbit. The Constitution does not say how the Senator is chosen, only that the state legislatures do the choosing. Thank you for the education!