What classes will you be taking in this SMP. If its like Georgetowns SMP, where they take med school courses, then those will count for your grad GPA. Although doing well in these classes look great, because they ARE med school classes, they will not add anything to your undergrad GPA assuming these are grad/med level courses.
Also, as stated by UMP, it depends on the school. If you apply to Georgetown, they will recognize that those are their med school courses, and can gauge your performance very well. However if you apply somewhere else, they may just see it as a grad level course which may be deemed as comparable or NOT comparable to med school courses. Which leads to your undergrad GPA.
Since the vast majority of people apply with only undergrad coursework, they would weigh your undergrad GPA more vs. grad GPA. This is why advisors and schools often tell you to take more post-bacc courses to boost your undergrad GPA rather than go to grad school. Don't get me wrong, grad courses are not inferior to undergrad coursework. Grad courses can only be considered a positive thing, but to what extent depends on the school, and your entire application.
There are a few non-trads out there that have PhD's where during interviews, their interviewers placed more relevance on their recent grad coursework vs. their undergrad classes. But at the same time, I can say that their degrees, GPA weren't the only factors that got them an interview and acceptance.
As much as I want to say that SMP coursework could make up for deficiencies in undergrad, it probably won't. You will need to prove to the adcoms through doing well in your SMP, and doing well on the MCAT, and if possible take upper division courses during your SMP. You realy need to reevaluate how you study. In terms of workload, OChem is nothing compared to what some grad courses are like, let alone med school courses offered through SMPs. If SMPs are anything like grad school, a B- could get you kicked out. So work hard, and hang in there!
