Since New Mexico enacted a new disclosure law last year, more than $800,000 in political spending has been publicly reported by nonprofit groups that in the past would have remained largely hidden.

It's a change that Secretary of State Maggie Toulouse Oliver calls "a huge victory." But Austin Graham of the Campaign Legal Center, which advocates for tighter regulation of money in politics, is more reserved: "What's on the books in New Mexico is not the most cutting edge, but it's undoubtedly a big improvement from the last decade."

The New Mexico experience illustrates that improving the transparency of how campaigns are financed can be done, but making progress often requires incremental steps that take a lot of time. What has happened in New Mexico is an example of what states across the country must grapple with when they seek to slow the influence of money over their own politics, at a time when federal regulation of presidential and congressional elections has shriveled.