Translation:It took twelve months.
It's not ケ, it's ヶ, a simplified way to write 箇. In order to count months, 箇月(or ヶ月) is used.
In addition to Marc's answer, ヶ is pronounced 'Ka', or sometimes 'Ko' (depending on what is being counted).
Number + Moon would indicate months as in January 一月. Therefore, a counter is used whenever the speaker mean months as a period of time.
Okay, so the word かかりmeans 'to take' right? Could you use it in a literal context? Like "I took the candy"? Or is it just for time periods?