Attorney Timothy McKeever, in a letter to broadcasters Monday, said they are under a "legal and moral obligation" not to air the new ads from Tea Party Express, which is supporting Joe Miller, the political upstart who defeated Murkowski in the August GOP primary.
A Tea Party Express spokesman said his initial reaction is that the group stands behind the ads.
At issue is an ad the group unveiled Monday, entitled "Arrogant Lisa Murkowski - You Lost!" It seeks to paint Murkowski as more interested in political self-preservation than in serving the interests of Alaskans. It also claims she didn't "earn" her Senate seat and that she "tried to manipulate the Libertarian party into giving her their slot" on the ballot - claims McKeever called "materially false."
Murkowski was appointed to the seat her father held when he became governor in 2002; she won it in her own right in 2004.
Murkowski has said friends - without her direction - approached the party to see what it would take for her name to appear as a Libertarian candidate and that she was not about to change her beliefs for political expediency.
Scott Kohlhaas, the Libertarian party's chairman, said he did have a "get-to-know-you" with Murkowski's then-campaign manager, John Bitney, who could not immediately be reached.
Libertarian leaders waited for Murkowski to ask for a ballot line but she never did, Kohlhaas said.
The party didn't feel manipulated by Murkowski, he said. "Tempted, another story," Kohlhaas said Monday. "But manipulated, no."
Tea Party Express also made claims about Murkowski's record during the primary that she called mischaracterizations or lies.
For example, it repeated the claim - which Miller also stated - that she opposed repealing the federal health care overhaul. Murkowski vehemently denied that and pointed to her record to back her up. Both Tea Party Express and Miller have stood behind the claim, and the campaigns they ran.
Tea Party Express spokesman Levi Russell said the group has tried to "put out the purest form of the truth." The ads unveiled for reporters Monday were finished over the weekend, and the group hoped to make ad buys that would have them on the air this week.
During the primary, Tea Party Express reported spending more than $550,000 to help Miller, a Sarah Palin-supported candidate who favors limiting the powers of the federal government to those outlined in the Constitution.
The group has pledged to do whatever it takes to beat Murkowski in November - including spending $100,000 or more on print and broadcast ads and direct mail.
"Lisa, we beat you once, and we will beat you again," chairwoman Amy Kremer said in Anchorage Monday. She called Murkowski a "political diva."
Murkowski has acknowledged not being ready for the impact the group would have. It ran seemingly ubiquitous ads in the primary's final stretch after touring the state for weeks, holding at-times sparsely attended rallies.
Murkowski promised to avoid a repeat this time. She is running ads aimed at Tea Party Express featuring people vowing not to be "fooled" again, saying the group is poised to drop a "dirty money bomb" and is trying to "take our seat."
Murkowski has called Tea Party Express an outside "extremist" group that "hijacked" the state GOP.
Eddie Burke, a former radio talk show host and spokesman for the nascent Anchorage Tea Party, said his group asked Tea Party Express
which he termed "powerful" - to return to Alaska to help defeat Murkowski. He said it did this because the state and country are worth fighting for.
Tea Party Express also is hosting a two-hour radio-thon Monday night, a rally and fundraiser of sorts for Miller, on KBYR in Anchorage. Russell said the group has done this in other states, too - taken over the airwaves with callers talking up their candidate. He said he could not immediately say how much the air-buy cost.
The group also hasn't said how much it has raised to support Miller since the primary. He has been one of three U.S. Senate candidates and political upstarts for which it has been making special fundraising appeals. The others are Christine O'Donnell in Delaware and Sharron Angle in Nevada.
Miller told ABC News and Politico that he doesn't support a federal minimum wage. He said that issue - like others - should be decided at the state level. He noted Alaska's minimum - of $7.75 an hour - is higher than the national minimum, of $7.25 an hour.
A 2009 state law calls for the minimum in Alaska to be 50 cents higher than the national floor.
Miller also has said unemployment compensation benefits aren't constitutionally authorized and need to be looked at.
Miller confirmed Monday in an e-mail to The Associated Press that his wife, Kathleen, received unemployment benefits "for a short period of time" after leaving her job as a clerk/secretary in his federal magistrate's office.
Miller was a part-time federal magistrate from 2002 to 2004. He said that due to the time commitments involved, it was not uncommon then for people who worked as both part-time magistrates and lawyers to have the same people working for them in both offices. He said in many cases, those employees included family members. He said he spoke with members of the federal court - even before applying for the job - about his wife and said he'd received approval to have her work for him.
Miller entered the Senate race in April because he said he believes the nation is at a crisis point, Washington is out of control, and the federal government is on the brink of bankruptcy. He has been criticized for recent disclosures that he and his family received government benefits in the past, including farm subsidies on land he owned in Kansas in the 1990s and low-income hunting and fishing licenses for him and his wife after they first moved to Alaska.
He said he's never denied that he has received benefits and said he isn't receiving them currently.