Is it ever possible to become a higher ranked seller than a larger competitor in your niche?

Is it realistic to ever be able to beat your competitor in monthly sales if they are already dominate in a specific product niche. considering that they already have at least a year of revenue and will probably have a much much much bigger budget for running ads constantly?

Or is there pretty much no shot and you will forever be under them, even though you may experience fantastic growth and generate meaningful revenue. I guess what I’m asking is, does the big fish always eat the little fish?

and a side question… how much competitors is TOO much anyway? 1 other seller? 2? 10? 20?
I thought my niche was not too bad and id be able to swing it and become a 5th place best seller, but now I’m having a little bit of doubt thinking I may have been a bit overzealous, or even ignorant to how much money needs to be invested to get something running….

I’m still confident I can market better than them, but my bag of tricks (and wallet) isn’t unlimited afterall