Republicans are now threatening to block confirmation votes on key Health and Human Services nominees unless the department again allows Medicare plan providers to disseminate information about possible cuts to the program.

The political standoff began Friday when the Center for Medicare and Medicaid Services announced it would investigate Humana, a leading provider of the Medicare Advantage program. At issue was whether the firm violated federal laws when it mailed letters to beneficiaries urging them to press their lawmakers to vote against possible plan cuts, which the Senate Finance Committee's healthcare reform bill might authorize.

Humana quickly cooperated with the investigation, but by Monday, CMS had directed all plan providers to cease and desist similar information campaigns. That move enraged Republicans, who quickly labeled the new rule a "gag order."

"And at the end of the day, seniors ought to get as much information about what is happening in this program as any other American," House Republican Leader John Boehner (R-Ohio) said at a press briefing on Wednesday. "And having the Medicare folks down at HHS deny them the accurate information that their insurer is sending them, I think is wrong."

Senate Republicans, however, upped the ante on Thursday. In a letter to HHS Secretary Kathleen Sebelius, they called CMS' directive unconstitutional, and they pointed to a series of previous legal decisions that upheld the right of Medicare companies to mail political messages to their subscribers, provided those information packets were not paid for using premium dollars.

Urging an end to the so-called "gag order," the eight lawmakers also asserted, "we will not consent to time agreements on the confirmation of any of your nominees to your department or associated agencies."

The threat temporarily jeopardizes a number of nominees and positions. Four candidates have been referred to committee that has jurisdiction: assistant secretary for Resources, assistant secretary for Planning, assistant secretary for Legislation and commissioner of the Administration for Children. One position -- the Surgeon General -- has been announced, but the White House has yet to submit the formal paperwork to the Senate.

Five spots remain totally vacant, and thus, temporarily frozen -- foremost among them, the director of CMS.

The GOP's issued its warning while Senate lawmakers on the Finance Committee trudged through the countless amendments to Chairman Max Baucus' (D-Mont.) healthcare reform proposal. One of the committee's key GOP members -- Sen. Chuck Grassley (Iowa) -- signed Thursday's letter, a move that could electrify an already tense markup process.