AUGUSTA, Maine (AP)   Maine could collect data on how ballot campaign groups pay for petition signatures under a bill facing Democratic Gov. Janet Mills.

A Republican’s bill would require groups to provide the state a list of individuals paid to circulate petitions, and report the “method” of compensation.

Republicans critical of the influence of out-of-state advocacy groups have fought to reform Maine’s referendum process. Maine voters in recent elections have approved marijuana legalization, Medicaid expansion, minimum wage hikes and a new ranked voting system.

The bill originally would have banned groups from paying circulators based on how many signatures they collect.

The Senate sent the bill to Mills Tuesday.

Mills recently signed a Republican bill requiring public hearings on ballot initiatives. The Maine Heritage Policy Center called it a “monumental victory for transparency.”