A spray-dried catalyst precursor composition and method of making a spray-dried catalyst precursor composition with an inert filler, magnesium, a transition metal, solvent, and one electron donor compound. The catalyst precursor composition is substantially free of other electron donor compounds, the molar ratio of the electron donor compound to magnesium is less than or equal to 1.9, and comprises spherical or substantially spherical particles having a particle size of from about 10 to about 200 m. Catalysts made from the spray-dried catalyst precursors and polymerization methods using such catalysts are disclosed.