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).
The first thing I want to say about cover letter format is when it comes to cover letters one size most certainly does not fit all. Although you can and should follow a format with your cover letter you should individually tailor each cover letter towards the job that you are applying for.