After pressure from Senate Finance Chairman Max Baucus (D-Mont.) senior committee staff, the Laborers International Union of North America has done an about-face and will pull its television ad buy targeting Baucus and Senate Budget Chairman Kent Conrad (D-N.D.) starting Wednesday.LIUNA, a union representing construction workers, had planned to run an ad on broadcast and cable television stations in Montana and North Dakota this week, imploring Baucus and Conrad to not tax health insurance benefits to help pay for health care reform.The 30-second spots had been set to air Tuesday through Thursday, with additional radio ads running through the July Fourth weekend.The spots are now expected to run only Tuesday. Sen. Baucus office reached out to LIUNA with a request to meet and attempt to resolve the health care tax issue, LIUNA spokesman Jacob Hay said. The Senators office requested that we stop the ads until that time.We agreed to do so and expect the ads to be held back starting [Wednesday], he added.The union is also now doing an additional ad Wednesday targeting Sen. Chuck Grassley (R-Iowa), the ranking member on the Senate Finance Committee.This is hardly the first time that Baucus aides have stepped in to shut down public opposition by health care stakeholders. Over the past several months, Russell Sullivan, the top staffer on Finance, and Jon Selib, Baucus chief of staff, have met with lobbyists, signaling that their clients should keep their powder dry until there is a final proposal if they want to remain at the negotiating table.Labor unions are strongly opposed to taxing insurance benefits, arguing that it could jeopardize employer-provided health plans. Baucus and Conrad are exploring ending the federal exclusion that protects employer-provided health insurance benefits from being taxed as regular income.