Early returns show voters in several Colorado cities rejecting several ballot measures backed by deep pocketed interests.

Most surprising was a green roof mandate that was maintaining a thin lead of 52-48 percent as of 11 a.m. on Wednesday.

The returns showed a thin margin in favor of requiring buildings in Denver that are more than 25,000-square-feet install either rooftop gardens, or a combination of gardens and solar panels.

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The measure was opposed by Mayor Michael Hancock and developers spent heavily to defeat it.

In Broomfield, voters appear poised to approve Ballot Issue 301, which would require the city to consider public health impacts when approving oil and gas drilling.

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The ballot issue, which drew significant spending in opposition by the oil and gas industry, was favored by voters 57-43 percent as of 11 a.m.

Fort Collins voters signaled support for municipally-owned broadband services, with 57 percent of voters -- as of 11 a.m. -- in favor of Question 2B, which was opposed by the cable industry.

Big money wasn’t completely stymied in early returns on municipal ballot issues.

In Denver, seven bond initiatives totaling $837 million were maintaining sizeable leads. All were touted in a well-financed ad campaign fronted by Mayor Hancock.