CHEYENNE, Wyo. (AP) — Proponents of a constitutional amendment to limit political campaign contributions have fallen short of getting their initiative on the 2018 ballot in Wyoming.

They are now shooting for the 2020 statewide ballot to get their initiative calling on Congress to propose amending the U.S. Constitution or to convene a constitutional convention on the subject.

The Wyoming Tribune Eagle reports the effort is being spearheaded by Wyoming Promise, an affiliate of American Promise.

The goal of the effort is to amend the U.S. Constitution to ban political contributions from corporations.

In May, Wyoming Secretary of State Ed Murray certified a state ballot initiative sponsored and authored by Wyoming Promise. The ballot initiative needed to gather 38,818 signatures to get on this year's ballot but so far had only collected about 10,000.