Transportation Secretary Ray LaHood will continue his congressional tour this week to discuss the administration's six-year, $556 billion surface transportation plan outlined in the fiscal 2012 budget request.

LaHood will face two of the panels crafting the Senate version of the transportation program -- Environment and Public Works, which oversees highway policy, and the Commerce, Science and Transportation Committee, which handles road safety and freight. He will also testify before the Appropriations Committee, which is reviewing the proposed budget.

The secretary was scheduled to meet with the EPW and Commerce committees last week, but both hearings were postponed.

The White House plan for a surface transportation reauthorization would give greater weight to public transit and rail projects, putting them in the renamed Transportation Trust Fund alongside highway projects. The proposal also creates a National Infrastructure Bank and sets aside $4.1 billion for livability projects.

The $556 billion price tag represents a 66 percent increase in transportation funding, committing roughly $270 billion more over six years.

If last week's hearing with the Senate Budget Committee is any indication, LaHood will face serious questions about the administration's lack of a defined funding source. The administration left funding decisions for the bill up to Congress, although LaHood, a former House member, has said he will participate in discussions.

Budget ranking member Jeff Sessions (R-Ala.) poked fun at the administration's proposed "not gas tax tax" and said that without a funding source, he saw a "zero percent chance" of passage.

The surface transportation program is currently funded through a gas tax that has not been increased since 1993. President Obama has said he will not increase the gas tax during difficult economic times and is committed to finding another funding source for transportation.

An aide for the EPW Committee said the hearing would focus on "building consensus" for the new bill. Commerce Committee members will also look at new safety regulations in the bill.

EPW Chairwoman Barbara Boxer (D-Calif.) and ranking member James Inhofe (R-Okla.) are said to be working on their own six-year reauthorization to replace the existing bill, which expired in September 2009 and has now been extended until Sept. 30.

Obama wants to use the transportation bill as a job-creation tool to spur more investment and economic activity.

LaHood may also face questions about the proposal's focus on transit and high-speed rail and the creation of the infrastructure bank.

Schedule: The Commerce, Science and Transportation hearing is tomorrow, March 8, at 2:30 p.m. in 253 Russell.

Witness: Transportation Secretary Ray LaHood.

Schedule: The Environment and Public Works hearing is Wednesday, March 9, at 2:15 p.m. in 406 Dirksen.

Witness: LaHood.

Schedule: The Appropriations hearing is Thursday, March 10, at 9 a.m. in 138 Dirksen.

Witness: LaHood.