Short answer is of course you can! Keep working on the grades. HYPMS is crazy hard to get into for anyone, so nobody can predict that. But top 20 for sure especially if you have a demonstrated academic interest that fits well into one of your targeted schools. Also, if you are able, choose a school (if you are financially able and truly interested) that will give weight to an early decision application and go for it. Have an ED II ready as a backup and realize that you can also get in regular decision if I and II fail. Note that this strategy may not work well if you target early action schools like HYPMS. It will work best at schools that seek ED applications like Vandy and WashU. Finally, don’t forget to consider liberal arts schools. Good luck!