The $478 billion apportioned for spending on transportation infrastructure over the next six years in President Obama’s $4 trillion budget proposal [FY2016] may well be hefty enough to compel Congress to at last draw up and pass a massively funded, multi-year highway bill of its own.

Obama’s ambitious plan lays out how he would achieve the goal stated in his State of the Union address last month to advance “middle-class economics.”

While Republican leaders on Capitol Hill may view the overall proposal as merely a starting point for negotiations, the sheer size and scope of the infrastructure-investment component rolled out by the President sharply raises the political stakes for the GOP to deliver an equally bold response detailing what they will legislate to improve highways and bridges as well as railroads and ports.

“To spur economic growth and allow states and localities to initiate sound multi-year investments, the budget includes a six-year, $478 billion surface transportation reauthorization,” according to the proposal as published by The White House.

In addition, per the document, the budget would also invest in infrastructure through “tax incentives for state and local infrastructure investment, a new infrastructure bank and other initiatives,” including support for the Build America Investment Initiative, an interagency effort “to increase infrastructure investment and promote economic growth by supporting public-private collaboration in major infrastructure sectors such as transportation…”

At least when it comes to roads and bridges, Obama’s budget target is starting to attract plaudits. For example, a key lobby on highway-spending issues, the American Association of State Highway and Transportation Officials, was quick to “commend” the proposal shortly after its public release.

“We applaud the president and his administration for their leadership that has set the stage for a serious discussion about the next surface transportation bill," said Bud Wright, AASHTO executive director, in a statement.

"We know the hardest conversations will involve how to fund infrastructure investments,” he continued. “We look forward to working with the President and Congress on developing a new transportation bill supported by a long-term, sustainable source of funding."

AASHTO added a note of urgency to its commendation – pointing out that “the Federal Highway Trust Fund and the current surface transportation authorization are scheduled to expire May 31.”