Oh old movies... when the soldiers are losing, out numbered against the (possibly politically incorrect) foe, just wait for it... The Cavalry arrives on shiny horses to slay the enemy!
It might sound cliche, but be the cavalry. Be the person that can show up and solve the problem. Maybe I'm just too deep into engineering, and we love solving problems. We live in a world where people want someone else to solve the problem. Seth Godin's book Linchpin is a good one because it's about picking yourself, regardless of your place in life, to make a difference in your world. It's a simple question, who can make the biggest difference in your world? You.
In other words, be the cavalry. Even if you solve the problem and no one seems to care, maybe they will at a later time. Step forward often enough to "save the day" and soon enough you will get the respect to solve more problems, and your voice will have more respect. There are opportunities every day to improve your vocation. Pick yourself, be the cavalry.