Missouri gubernatorial candidate Chris Koster has thrown his support behind a November ballot initiative aimed at reinstating campaign contributions limits.

While he served in the state Senate, Koster voted twice to remove the limits and has since opposed multiple attempts to reinstate them. He claims his change of heart is a result of a shift in the way Missouri campaigns are funded.

A decade ago, there were few, if any, large contributions; he believed removing limits would improve transparency. Now, however, it is not uncommon to see seven-figure contributions funneling through committees, with no mechanism to effectively identify the original contributors.

The proposed ballot measure would ban direct corporate and labor union contributions and limit individual and committee contributions to statewide candidates to $2,600 per election. Contributions to political parties would be capped at $25,000 per election.

The measure was certified for the November ballot, but still must overcome a legal challenge.