After a City Council vote Thursday night, Tempe is moving ahead with an ordinance that it hopes will limit the influence of so-called "dark money" on its municipal elections.

The proposal would require groups making independent expenditures of more than $1,000 to reveal the funding source.

Councilwoman Lauren Kuby spoke at the council meeting before the vote. She has been a driving force for the proposal.

Tempe’s move seems like a groundbreaking one, but could it signal a trend?

Ned Foley is an Ohio State University law professor and campaign finance expert.