There are allot variables in the cost \benefit of a game production, i have not been apart of the gaming industry formally or informally. There are 3 crucial varietals which are: Demographic, cost of game (start to finch) and finally marketing. (btw English is not my main language. sorry fore the spelling errors.)
Demography of the wasteland gamer marked is the fans of fallout 1, 2 and of course wasteland. Which has been in existence long time, which gives synergy between the games in exposure. The game sales fore fallout and fallout 2 is between 125-150k on each, later the game has generated longterm sales. The unique chase of fallout it the longevity of the sales they still generate and will generate.
Cost of game. i have no clue, although they seem to know what they are doing so probability of overshot seems small.
Marketing today is really simple cost and benefit, like a high end movie cost 200m to make so it is given 75m to marked it self. (generally 40% is put to marketing) Sometimes they use more money to marked a movie then the cost of the movie it self, like some of the Kevin Smith movies (mirmax studios). Marking is knife between Red numbers or black numbers. Games today are very much like movies where marking are big part of the process. The demographic of wasteland 2 are niche and many old fans dying to see it. Best way to promote the game is probably interviews, art work and viral marketing (you tube, social media and website ala flash games or something fun related to the game). So if they play it perfectly they may get nice number of sales but they wont become mainstream.
other factors which are not important right now since it is funded already or other means:
Enter Market how? (done in a fashion)
Upkeep costs? (patch, add ons and mod comp. this process comes after the game is out.)
Staff? (idk)
Legal Fees? (they have the license to make wasteland, although they have probably a lawyer seeing things true.)
Trademarks? (idk)
Patents? (idk)
Exit Strat? (This is done by people what knows what they are doing, hopefully they do not have to make one

.
Finlay i would just say i do not have the numbers of the sales, the hard numbers but guesstimate on similar events. So i think it has a demographic of 200-500K people that will buy the game first release and live a long time after it is done. The volume which are funding the game now should be viewed not as the main buyers (50k to 60k). It has been fun watching, the kikkstarter campaign now i hoping fore 3m or more.