How are the tickets being printed and who is controlling the tickets between buyer and seller?
Say the lotto agent receives some allotment of tickets from the lotto headquarters. I'm not sure how the drawing is determined (of course I assume it only happens on the day of the draw and is similarly random to other lottos?), but if you were interested, and capable, of fixing that draw, you already have the power to choose where your determined winning tickets go.
If you control distribution of pre-determined numbers, then one expects that you control where those numbers go. Either directly determining winners in a region (Hey mom, uncle, dad, steve, sally: Go buy x # of tickets at this gas station on Tuesday!) or greatly influence the odds of winning to a certain district.
I'm not saying it would be easy, but to me it seems to go from a double-blind level of confidence to a single-blind level.