Some Republicans have been defensive that the party has a strong anti-democratic bent. But the state GOP convention embraced it, putting it right in the party platform.
Senators were not elected by the people before the 17th amendment. The House of Representatives represent the interests of the people of their districts, so they were elected by the people. Senators represent the interests of their state as an entity, so they were elected by the legislature of their state or appointed by their governor.
The USA at the federal level is a republic, not a direct democracy. We elect those who vote upon the federal laws. I'm that easy, some worry that more voice of the people and less of the state as an entity runs afoul of that notion and the constitution itself.
I understand that point from a limited perspective, but it is now frequently used as a way to ignore constituents and beat the drum of fascism. Do not trust a politician that is worried about the 17th amendment. That ship sailed a century ago.