This paper finds welfare- and revenue-maximizing mechanisms for assigning a divisible good to a population of budget-constrained agents who have independently distributed private valuations and budgets without unit-demand. Both optimal mechanisms feature a linear price for the good. The welfare-maximizing mechanism additionally has a uniform lump-sum transfer to all agents and a higher linear price than the revenue-maximizing mechanism. This transfer increases welfare because it ameliorates the key difficulty in the aforementioned setting: agents with high valuations cannot purchase an efficient amount of the good due to their budget constraints. Finally, in an extension, I relax the independence between valuations and budgets. In an online appendix, I consider production and large finite markets.