After 14 months as president of the National Association of Broadcasters, David Rehr has put himself smack at the forefront of an assault against the proposed merger between XM Satellite Radio and Sirius Satellite Radio. The effort, lobbyists on both sides of the fight say, will be the first major challenge for Rehr and the team he has installed.

The campaign against the merger is likely to last for months. And NAB members, merger proponents and Capitol Hill leaders are watching to see how Rehr, who before joining the NAB built a reputation as a scrappy GOP lobbyist and adroit fundraiser, leads the charge.

The NAB’s opposition to the proposed deal is taking center stage this week as its members are in town for a previously scheduled lobbying blitz. Those broadcasters, many of whom are walking the halls of Congress sporting buttons that say “No Satellite Radio Monopoly,” will get the opportunity to see Rehr testify today for the first time ever as the NAB’s chief during a House Judiciary antitrust task force hearing.

“There is a lot at stake here for the future of broadcast radio with this,” said Greg Rohde, president of the lobbying and consulting firm e-Copernicus, which represents a coalition that includes XM. But Rohde’s coalition is not involved in the merger. “There’s just an awful lot happening that affects the broadcasting industry. Years down the road, we may look back and see this as being a very formative period for broadcasting.”

NAB spokesman Dennis Wharton said Rehr was unavailable for comment because the group has 500 broadcasters in town for this week’s events. Wharton said the merger issue is “extremely important” to the group’s radio members — many of whom are taking the opportunity of the lobby day to visit their Members to build support against it.

“We don’t think the government ought to be endorsing or sanctioning monopolies,” Wharton said.

A broadcast industry lobbyist, who would speak about the issue only on condition of anonymity, said the battle is the NAB’s to lose.

“From a pure antitrust perspective, the NAB should win this fight,” this lobbyist said. “It should not be considered a Herculean triumph if NAB were to prevail in its opposition.” But, this lobbyist said, if the NAB’s side loses, “I think one could say that the NAB has not distinguished itself in the lobbying context, and it would send a very negative signal for NAB’s leadership under David Rehr.”

Since taking over the NAB in late 2005 from longtime President Eddie Fritts, Rehr has faced some criticism from Democrats on Capitol Hill.

A communications lawyer, who would speak only on background, said that he attended some of Tuesday’s NAB events at the Mandarin Oriental hotel where Energy and Commerce Chairman John Dingell (D-Mich.) and Rep. Ed Markey (D-Mass.), chairman of the Energy and Commerce subcommittee on telecommunications and the Internet, both spoke to the group’s members.

When Dingell spoke, this communications lawyer said, he told the audience of broadcasters that they have been well-represented over the years by advocates such as Fritts and Vince Wasilewski, omitting the name of the group’s current chief.

“Anybody who knows what’s going on immediately picked up on the insult,” this communications lawyer said. The lawyer added that later in his speech, Dingell referenced that the NAB had, for the first time in his memory, sent a letter to all Members of Congress urging support for a 2005 budget reconciliation bill, something that many Democrats did not support. “He was registering his displeasure,” the lawyer said. “Members of Congress don’t forget.”

A spokeswoman for Dingell could not be reached for comment.

But Markey — whose subcommittee is holding a hearing on the satellite radio business March 7 — and other Democrats publicly have signaled their skepticism of the merger, and some lobbyists in the industry said this could be an opportunity for Rehr to connect with Democrats.

“In light of his problems with Congressional Democrats, the challenge to him is whether he can use the fact that he and Democrats would appear to both be against the merger as a means to build a new bridge to Congressional Democrats,” said an industry source who is not working for or against the merger and does not represent the NAB.

NAB’s Wharton said: “Every time there is a public policy issue, NAB and David Rehr see it as an opportunity to build relationships on Capitol Hill on both sides of the aisle.”

Other lobbyists said that Rehr’s ties to the GOP, a party that tends to be friendlier to corporate consolidation, could end up helping the NAB’s cause by potentially lining up GOP support for the NAB’s position.

A lobbyist in favor of the Sirius-XM merger said the NAB’s opposition is just part of the group’s larger skirmish with satellite radio. The NAB also is pushing for legislation, sponsored by Reps. Chip Pickering (R-Miss.) and Gene Green (D-Texas), that would further limit satellite stations from running local programming.

This lobbyist and others involved in the fight said the NAB “has engaged their big guns.”

Since Rehr took over the NAB, he has changed the in-house lobbying lineup of “big guns.” The government relations department now is headed by Douglas Wiley and includes Republican Mildred Webber, who joined from the office of House Minority Whip Roy Blunt (R-Mo.), as well as Democrats Laurie Knight, who worked with Rehr at the National Beer Wholesalers Association where he was president, and Mike Mullen, a former aide to Rep. Mike Doyle (D-Pa.).

Rehr also keeps outside lobbyists on retainer, including former Rep. Max Sandlin (D-Texas) and Republican Dan Mattoon of Mattoon & Associates, among others. And NAB retains Wiley Rein, the law and lobbying firm of Douglas Wiley’s father, Dick Wiley. However, Wharton said Wiley Rein is not lobbying for NAB’s position on the merger because it also represents Sirius in pushing for the merger.

“It’s a bipartisan talented team, and they’re doing a great job,” Wharton said.

Said a lobbyist who works for one of the satellite companies: “There is a concerted focused effort to move out against this proposed merger and inflict as much pain and get the most flesh that NAB can out of this. If they don’t stop it, they want to make sure they get a pound of flesh out of it.”