[Dave S]

37 states already have similar amendments on the books--that's one fewer than needed to ratify a Constitutional Amendment.

I doubt that they are true constitutional ammendments. What you are probably referring to are state laws passed by state assemblies. These require 51% for passage where as constitutional ammendments typically require super majorities.

[AFPhys]

In many states, approval of a US Constitutional Amendment is done by a simple majority of the state's legislatures or by a popular vote. Neither of these are a supermajority issue.