I'm a few years older than you and in a similar/identical field—digital marketing.
At 25, I was stuck in the same salary range you are currently for a while—50s to mid 60s. In my late 20s I was able to jump exponentially and you can probably do the same. I'm in the B2B IT software vertical, which generally has large marketing budgets.
Since you've mentioned you are up for a promotion soon, I would focus on exhibiting and documenting your unique value to the company in the next few months leading up to the promotion, and be sure to present some data about your achievements to your boss in a 1:1 around the time he is writing your eval. If he comes in with a lower raise/title than you expect, you can always ask for more while giving examples of how you've added value above and beyond your job desc.—it depends on your relationship with your manager, but this at least shows that you want more/are an A player and should be compensated as one.
If you're in the most expensive city in the U.S., there also should be plenty of local opportunities in better paying verticals. With your IS background you'd be a shoe-in for B2B marketing positions in tech/software if you're not in that industry already.
Finally, I would look at ways to expand your experience/responsibilities beyond digital advertising to more general digital marketing where possible. This could give you more opportunities to move laterally into higher paying positions, or vertically into management, while staying in the functional area you enjoy.
