The time for opening the polls for the purpose of conducting a primary election shall be 7:
20 Del. Laws, c. 393, § 18; 22 Del. Laws, c. 285, § 1; 27 Del. Laws, c. 66, § 1; Code 1915, § 1692; 40 Del. Laws, c. 142, § 7; Code 1935, § 1780; 45 Del. Laws, c. 150, § 5; 15 Del. C. 1953, § 3105; 50 Del. Laws, c. 426, § 8.