How much power does the Senate Majority Leader have?

Following this question: Why is the Senate leader allowed to decide which bills to vote on? - how much power exactly does Senate Majority Leader have?

Let's suppose that the Senate is split 51-49 between the parties, and the majority party is split 26-25 between the hardliners and moderates. This means that the leader would be a hardliner.

Does this mean that even on an issue that has 74-26 support from the minority party and moderates, the leader can always preempt (or indefinitely postpone) voting, and there is nothing that 74 supporting senators can do?

P.S. I'm looking for any possible mechanism to overrule Senate Majority Leader, not the only ones coming from the office of Vice President.