Very interesting question. I have a domain name which comes as a #1 result for a smaller niche keyword from 336,000 results. From my calculations using Alexa, I would estimate that a site with an OVT traffic result of 100,000 and showing up as #1 on a search engine should receive around 2-2500 visitors per day.
For example, lets check the keyword "student loan". It has an OVT of 82,087. Now, on a google search for the same keyword we come up with 17,200,000 results with Sallie Mae ranking as the #1 search result. Sallie Mae has an Alexa rank of 15,788. Sites with a traffic rank of 3,000,000, IMO, get around 20 visitors per day. So most likely Sallie Mae receives a daily visitor traffic of around 5200 visitors per day. But it also has 57900 back links. So we could approximate the actual traffic from the search engine to around 2000, with the remaining 3200 coming via back links and ads.
So an OVT keyword of 100,000 with a #1 search result ranking should get around 2-2500 visitors per day.
