Some techniques to help you get the new marketing job that you're looking for:
1. Resume Search Engine Optimization -- if there is a type of job that you're looking for, then your resume better include the keywords associated with that job in it. Keep in mind that when you're optimizing for search, you need to think in terms of how the person on the other end would search in order to show up. But more importantly, if you're looking for a specific type of job -- knowing what you know about the HR screening process -- you probably need the title of that job in your resume. How you stick it in there is an interesting challenge -- particularly if the role appears to be a tangent from your current resume. Like search engine marketing, if you take a user to a page that doesn't match their search, you're going to have a high bounce rate, and that has the potential to impact you across the category. In that way, if you think of resumes like web pages, assume that a recruiter is like a human version of the Google page rank algorithm -- tricks that elevate your rank today have the potential to crush your rank in the future -- focus on good content.
Of course, the challenge with this is that good content for search engines is not always good writing and design for people -- and many people haven't caught up to this yet. It's entirely likely that the things that will help a recruiter find your resume are also the things that will make them reject you when they look at it -- search engine optimized resumes don't necessarily match "traditional resume style". Let me know if you've come up with some good strategies for this.
2. Respond to job postings with a resume that's optimized to match the listing -- this is an important technique to keep in mind if you have any hope of getting past some "front line" recruiter and human resources filters. I've spoken with friends who recommended highly qualified candidates for internal organization openings -- only to see their resumes not make it past the first screening. Then, the same candidate sail through the process on a less matched position with a revision of their resume to match the specific listed "requirements". The point here is that requirements are a checklist used by the people who run the filter -- and they don't interpret that checklist or look for shades of capability.
Of course, moving beyond the how-I-try-to-be 'legal' disclaimer, consider "stretch your background" from a marketing point of view -- specifically, what exactly are you saying when you say "stretch your background." Forget about the making stuff up part -- what about that project team that you worked on, whose idea was it to add that feature? Was that you or the team? Or how about something like CRM -- if you worked three years at an organization that heavily used CRM, does that really make you more of an expert than the guy that set-up and configured Salesforce.com, only to watch the sales team not use it? The reality of these hypotheticals is that we work with real world examples like these every day. We work with people who take credit for our work or don't contribute to group processes. And, in the marketplace of your career, your competition includes those people.
Typically when your marketing a product, you don't have to tell you're potential customer about all of the negatives, the features that underperform, or the nuanced aspects of how the product doesn't work. Think about what might happen if you were buying a used car and you could see a detailed view of every moment of the car's history -- would your potential customer rule the car out because of that time when the car drove to Lake Tahoe, or maybe because of that time the car went over that speed bump at 20 MPH instead of 10?
Again, my point in all of this is not to misrepresent the product that is you. When you are selling you, you need to remember that you're taking your prospective employer through a selling process. And one of the first stages of that process -- the resume / cover letter gateway -- is early-stage selling, and you need to be concientious about controlling your message.