The going rate

Ryan Cleary writes in the latest Independent, asking:

The thing about donations is that they could be seen as a way to curry favour with the electorate. A politician could use a pot of donation cash as a tool to help remain in office, to buy votes — that’s the simple truth of it.

...

Ask yourself this: how many votes could $560,000 buy?

Well, according to Elizabeth Marshall (CBC Radio .ram audio file, I.P. Freely mash-up)

I think I gave money to anybody who asked. If I could do it. It would have been small amounts, maybe five dollars or ten dollars. Or twenty-five dollars.

Which means, to answer Ryan's question, that $560,000 could buy 112,000 five-dollar votes, 56,000 ten-dollar votes, or 22,400 of the high-class 25-dollar votes.