[duffbeer703]

If the Congress is corrupt, than the state legislatures are a corpulent sewer of corruption and graft. Anything that takes power from them is generally a good thing.

The upside of direct election is that at least there's a chance that good Senators, not subject to the petty whims of the state houses might make better policy. State legislatures were/are generally the products of political machines and tended to appoint Senators who would advance their aims.

In the 21st century, the power of the corporations, unions and trade associations to manipulate the electorate via mass media is at least as powerful as the political machinery that the 17th amendment attempted to fight.