A bill to tighten up the law around campaign communications that have slipped under the radar of Colorado’s campaign finance system was signed into law Tuesday.

Senate Bill 68 makes two changes to how campaign mailers and other printed materials disclose who pays for them.

The law closes the door on a loophole for communications delivered between a primary election and 60 days before the general election, a problem that surfaced in 2016 after lawmakers moved the state’s primary from August* to June.

Current law requires that communications sent out by candidates and campaign committees during certain periods clearly identify the candidate and who paid for the communications — that’s the “paid for by” line you see on TV ads or on mailers or social media.

In addition, communications about a candidate must disclose who paid for it and whether the candidate is supported or opposed. This information is contained in campaign finance reports filed with the Secretary of State’s TRACER system.

But these rules applied only to the 30 days before a primary election and the 60 days before a general election; they do not apply to the roughly three-month period in between.

Senate Bill 68 will close that loophole by requiring that communications costing more than $1,000 must disclose on TRACER who paid for it. It would cover anything paid for 30 days before the primary through the November general election.

In addition, under the measure, the communication itself must include the name of the person or entity that paid for it. The only exclusion, supporters said, would be for items like bumper stickers or buttons, because they are too small to include that information, as well as op-eds and news articles.

RELATED: Campaign-ad disclosures would tighten under Colorado Senate bill

In the House, Democratic Reps. Mike Weissman of Aurora and Lisa Cutter of Evergreen sponsored the bill, which was unchanged in its trip through that chamber. The bill got four Republican Senate “yes” votes although no House Republican voted for it.

The law goes into effect on Aug. 2 unless challenged by a citizen-driven ballot initiative.

Correction: An earlier version said Colorado’s primary was in March.