I've been regularly donating $30 every month I'm able to (which isn't as often as I'd like due to medical bills and increased living expenses in the last year) for what it's worth, on top of my KS backing. I'm sure many here do similarly, or even more. Sadly, it's the huge mass of the rest of the backers that would have to participate to make this happen.

Still, I firmly believe the game can and will be awesome - if not EVERYTHING we hoped for SIII to be - without reaching that sum. If anyone knows how to frugally micromanage a budget, it's Yu.

it's easy on paper..
but those who already participated are not necessarily ready to pay more unfortunately.
some of them is OK with the budget as it is. some of them love the game but not to the point that some of us would go for support. some of them don't even care about the franchise but they want to support the fans. or newcomers whom are interested in the franchise and payed the basic price to get the game.. etc

initially i donated about 2,600$ in kickstarter campaign and i wish if i could do more during that period.
when the Paypal campaign begins i had fantasized in my mind that with Paypal donors + 5000 to 10000 people whom are willing to continue the support after Kickstarter we could do miracles! (i mean 5000 X 50$ = 250,000$ per month just from existing backers!) so i continued my support in the first two months (100$ each) but unfortunately i overestimated the numbers and it was below below my expectations even though i tried to be realistic as possible as i could (there when i completely gave up on this)