[x]

The choice was either to allow the popular election of Senators, or to watch the Senate, an "undemocratic" body, lose power. For inevitably, a Senate still chosen by state legislatures would increasingly come to look illegitimate to voters.

I'm not sure that the Senate did look after the interest of states before the Amendment was passed. The growing national economy helped make the Senate more representative of economic interests than of state governments.

What changed most with the Amendment was that Senators, having won state elections, came to think of themselves as presidential timber. Before that, Senators didn't have to be popular or attractive vote-getters and hence were rarely considered as presidential candidates.

[Tolerance Sucks Rocks]

For inevitably, a Senate still chosen by state legislatures would increasingly come to look illegitimate to voters dumbed down by decades of pro-democracy propaganda and public education.

Fixed it.