I'm not sure there's an exact number, obviously it would have to be significant enough to where Konami would say "hey, we have (x number) of people who would buy this game". They wouldn't make a new one if, say, 50 people signed it. 50,000? Now you're talking.

And I need a hot woman to walk through my door. Some things just aren't gonna happen though. Such is life

There are ways....

I'm not sure there's an exact number, obviously it would have to be significant enough to where Konami would say "hey, we have (x number) of people who would buy this game". They wouldn't make a new one if, say, 50 people signed it. 50,000? Now you're talking.

Run a commerical that will make Konami take notice

I've mentioned it before, but I have spoken with/interviewed Jack Merluzzi in the past...and I do work in software...and I have a decently large network of software/developer types. Im sure I can dig up a friend-of-a-friend that works for Konami US. Or, ideally, get Konami to let me run a division that re-does the game for Wii U and PS4.

Don't underestimate the power a small but dedicated fanbase has. A few years ago, game companies would have looked at mobile games as worthless, and the old 8-bit era games as catering to a group of NES-loving loser 30-year-olds. Now both are big moneymakers. What was the game of the year in 2013 - X-Com, a remake of a game with a relatively small, but INCREDIBLY dedicated fanbase. Not only did they do the game, but PVP, enhanced versions, and DLC packages.

Sports games are a harder nut to crack, as most of the money and effort goes into getting the average 18-32 year old hooked on MADDEN or The Bigs or something similarly graphics and play driven. But the key is to convince Konami that not much is needed - bug fixes, minor improvements, new rosters...and that's it. Recouping the investment with some profit on a version every 2 years should be doable, and easily. ..the odd years could be handled with DLC.