The $10 million earmark was altered after Congress approved the massive 2005 highway funding bill before it went to the White House for President George Bush's consideration, Young's staff acknowledged to The Washington Post. (NYSE:WPO)

Democratic and Republican leaders alike endorsed the move, which observers said could be the first step in seeking a criminal investigation by the Justice Department.

Young, chairman of the House Transportation and Infrastructure Committee at the time the earmark was inserted, "has always supported and welcomed an open earmark process," a spokeswoman said. "If Congress decides to take up the matter of this particular project, there will be no objection from Mr. Young."

Young's critics said the motive for the provision on an Interstate-75 interchange project near Naples, Fla., was campaign contributions from real estate developers who own 4,000 acres of land near the proposed interchange.

The version approved by the House and Senate mentioned "widening and improvements" for I-75 in Collier and Lee counties. The bill sent to the White House indicated the money was allocated to"Coconut Road Interchange/Lee County."