Odds of Getting In
Companies are always going to need marketing managers. Why? Because companies like to make money, and marketing managers are the ones who sniff out previously untapped consumers and figure out how to sell products to those people.
So, congratulations! If you're good at marketing and can survive ten years of being stressed out over how you, personally, are affecting your company's bottom line, then you should have no problem moving up from mere marketing minion to marketing manager.