Republican presidential candidate Michele Bachmann may be falling in the polls, but her invective continues to rise. On Thursday, the Minnesota Congresswoman posted an open letter on her website that accused the Obama administration of placing campaign contributions ahead of national security. In the letter, Bachmann told supporters that the White House had pressured an Air Force general to soften his testimony to a House subcommittee because the general was speaking against a wireless project being pushed by a company called LightSquared in which Minnesota-born billionaire Phil Falcone is the chief investor. Officers in LightSquared donated to Obama, Bachmann said, so the president gave them favored treatment for a project that could dismantle global positioning (GPS) equipment used by the military, farmers and consumers. She accused the president of the same thing she accused Republican presidential opponent Rick Perry of in a debate last week: "Crony capitalism." " Shockingly, General [William] Shelton [commander of the Air Force Space Command] revealed during the hearing that the White House pressured him to change his testimony regarding the jamming of the GPS signal," Bachmann said in her "Dear Friends" letter. "Shelton testified that the Obama Administration had asked him to say the effects on the jamming of the GPS signals could be mitigated when they cannot," Bachmann said. Bachmann was not in the room and the meeting was closed to the public. Bachmann relied on revelations by Rep. Mike Turner, R-Ohio, who was in the hearing with Shelton and later gave the story to FOX news. Shelton declined comment on the allegations Thursday. "The testimony I provide to Congress as the commander of Air Force Space Command is and will be based on facts as I know them," he said in a statement. "What needs to be emphasized here is that life as Americans know it today relies on the critical precision positioning navigation and timing services GPS provides. Agriculture, banking, transportation, weather, national defense all proved to be significantly impacted by the interference we found through our testing to date of the LightSquared network proposal. Protecting the nation's critical infrastructure is the focus we should have on this issue." The Obama administration said the same thing in a strong rebuke of Bachmann's charges issued Wednesday. afternoon. "Every administration witness testifying at every hearing on LightSquared has been explicit in identifying the problems for GPS, and the need to resolve interference problems before LightSquared is allowed to move forward," said White House spokeswoman Joanna Rosholm. "It is not unusual for changes to be suggested to testimony as a result of the OMB [Office of Management and Budget] process. Indeed, that is fully consistent with OMB's longstanding role – which is to review all agency communications with Congress, including testimony, and to seek the comments of agencies with relevant expertise, to ensure consistency in the Administration's policy positions."