That leads to three axioms: 1. You can make yourself the obvious choice for the job and attract many offers, but to do it, you must be the candidate who maximizes every portion of your job packet to attract the recruiter's attention, so 2. You must have a system that gives you a cover letter format [http://coverletterhelp.info] and specific additional techniques optimized to get you calls, and 3. Your system needs to be automated so it creates cover letters very rapidly and very easily so you actually do it every time (and don't simply intend to do it).
Make yourself the obvious choice. Maximize every portion of your job packet to attract the recruiter's attention.