Could the next big push from broadcasters on Capitol Hill surround their desire to obtain multicast must-carry mandates for cable?

During his opening address to attendees at this year’s National Association of Broadcasters convention in Las Vegas, NAB President and CEO David Rehr said the group has started to take its multicast “message” to Congress, and that the effort has “been well received” by lawmakers.

In his speech Monday, Rehr also took on cable industry assertions tied to multicasting, in which digital TV spectrum is split into multiple streams.

“This is not a case where the pie is only so big and we want to eat the cable companies’ slices,” said the NAB executive. “Through the magic of compression technology, we are making the pie bigger by adding extra slices, extra programming. The cable companies intend to strip out our new programming because we’re in competition.”

Rehr added, “We’re not asking to take someone else’s property or programming. We’re simply asking that the cable companies not take ours. We’re simply asking that they do not take the anti-competitive step of stripping out our signals.”

And, as expected, Rehr criticized the proposed merger between XM and Sirius, a $13 billion deal still awaiting the regulatory OK. He said the transaction will not win approval.

“In 1997, when the Federal Communications Commission authorized two nationwide satellite radio operators, it specifically prohibited them from merging,” Rehr said. “The bad business decisions of XM and Sirius should not be rewarded with a government bailout in the form of a monopoly.”