Once you've persuaded others to join your coalition
, you've established a base that will legitimize your idea. Coalition members will then use their networks to evangelize for you.
Getting others to make changes and do things your way is risky and fraught with personal peril. Making your organization a better place is often at odds with personal advancement.
You can't do it without power. Just be sure to create power in and with others, as opposed to using power over others.