The main evidence it has supporting it is the a "post hoc, ergo propter hoc" claim (there was a bank crisis before the great depression). But this ignores a huge number of other factors which also contributed to the GD - massive ecological disaster, huge drops in trade caused by Smoot-Hawley et al, new anti-competitive laws and onerous regulations, new technology making millions of workers obsolete.
The claim that a banking crisis caused the GD is popular mainly because banks are easy to model. It's kind of the economic equivalent of looking for your keys near the streetlamp rather than in the dark alley where you lost them.
Please go read up on the New Deal as well as the Hoover administration (Hoover doubled the budget deficit in an attempt to spur recovery, resulting in FDR calling him a Socialist during the election campaign).
http://en.m.wikipedia.org/wiki/Causes_of_the_Great_Depressio...
Among other things (since you want to take a 100% Keynesian view), the government created sticky nominal wages and prices (with minimum wages and price floors). Hey, remember why Keynesian economics claims we need to print money?
Loose monetary policy during a drought is not just supported by Keynesians (who really emphasize more expansionary fiscal policy), and is definitely not a 100% Keynesian view. Monetarists, for instance, support it widely. As do other economists. Friedman supported it, as does Bernanke, Greenspan, Summers, Mankiw, et al. To claim that an expansionary monetary policy is 100% Keynesian is just absurd and distorts the positions of other economists.
Lastly, if you read your own link (to the Wikipedia article on causes of the GD), you'll discover that there are many proposed explanations (including, for example, protectionism).
That's it for me.
This precipitated a run on exchanging dollars for gold, a run that continued to collapse banks until FDR suspended exchanging dollars for gold.
Nobel laureate: http://en.wikipedia.org/wiki/Joseph_Stiglitz
Dissention: http://www.telegraph.co.uk/finance/recession/5045421/Geithne...
But the populist sentiment comes from that the lowest bracket of society is still not out of the recession. The recession is over in the technical meaning, but tell that to the down-and-out and see how they react. It's also not the case that the financial system is totally repaired, though thankfully it looks like the perverse incentives in home mortgages are going away, at least.
If by the lowest bracket you mean "the bottom 80%", then yes.