This article employs a simple model to describe bidding behavior in multi-unit uniform price procurement auctions when firms are capacity constrained. Using data from the New York City procurement auctions for power generating capacity, I find that firms use simple bidding strategies to coordinate on an equilibrium that extracts high rents for all bidders. I show theoretically and empirically that the largest bidder submits the auction clearing bid. All other bidders submit inframarginal bids that are low enough to not be profitably undercut. Inframarginal bidders decrease their bids as the pivotal firm's capacities and its profits of undercutting increase.