The unusual “blanket hold” placed on Obama administration nominees by Senator Richard Shelby, represents an effort to support a firm that has contributed more than $100,000 to the Alabama Republican over the course of his long political career, according to a Center for Public Integrity analysis.

Shelby reportedly initiated the blanket hold in an attempt to back a $35 billion tanker contract for Northrop Grumman and EADS; the plane would be built in his state.

The contract had been initially awarded to the companies in 2008, but was canceled after rival Boeing protested and the Government Accountability Office upheld the protest — forcing the Defense Department to rebid the contract. Shelby has been outspoken in support of granting the contract to Northrop Grumman and EADS. Shelby and Northrop Grumman have both objected to the Defense Department’s new rebidding process.

While by all accounts a Northrop Grumman contract would create significant numbers of jobs in his home state, Shelby’s initiative is also a move to secure funding for a company that has long funded him. The fourth-term Senator has received at least $108,233 in PAC contributions to his political campaigns and leadership PAC from Northrop Grumman’s corporate PACs. This includes contributions, dating back to his first Senate election in 1986, from the company’s political action committee and from the PACs of companies that are now part of Northrop Grumman.

According to the Center analysis, this level of support ranks Northrop Grumman as the seventh most generous institutional supporter over the course of Shelby’s political career.

By placing the holds, Shelby essentially announced he would filibuster any nominee sent by the White House to the Senate for confirmation. The White House lists more than 200 nominees who have not yet received a Senate confirmation vote.

Calls to the office of Senator Shelby were not returned by publication time. But in a statement to Talking Points Memo, a Shelby spokesman said the holds were “due to unaddressed national security concerns.” Among those concerns, he said, “is that nearly 10 years after the U.S. Air Force announced plans to replace the aging tanker fleet, we still do not have a transparent and fair acquisition process to move forward.” He said the senator was also “deeply concerned” that the Obama administration will not release funds already appropriated to the FBI to build the Terrorist Explosives Devices Analytical Center, a facility to be located in Alabama.

A spokesman for Northrop Grumman told the Center that the company “is very conscientious in adhering to all federal regulations and reporting requirements when supporting members of Congress. The company's contributions to representatives of both political parties are a matter of public record.”