1. Preheat oven to 350°.
2. To prepare cake, weigh or lightly spoon flour into dry measuring cups; level with a knife. Combine flour, baking powder, baking soda, and salt, stirring with a whisk.
3. Combine canola oil and next 4 ingredients (through eggs) in a large bowl. Beat with a mixer at medium speed 2 minutes or until well combined. Stir in ginger. Add flour mixture and ginger ale alternately to sugar mixture, beginning and ending with flour mixture, beating just until combined. Scrape batter into a 12-cup Bundt pan coated with baking spray. Bake at 350° for 38 minutes or until a wooden pick inserted in center comes out clean. Cool in pan 15 minutes on a wire rack. Invert cake onto plate.
4. To prepare glaze, place kumquats, 1/2 cup granulated sugar, and 1/2 cup water in saucepan, and bring to a boil. Simmer, uncovered, for 15 minutes, stirring occasionally. Strain kumquat mixture through a sieve into a bowl, reserving sugar syrup and kumquats.
5. Combine powdered sugar, dash of salt, and 3 tablespoons reserved syrup, stirring with a whisk until smooth; reserve remaining syrup for another use. Stir in kumquats. Spoon warm glaze over warm cake.