The Colorado House of Representatives passed one of the most important bills of the session – to pump billions of dollars into transportation – Tuesday morning with 36 hours left in the four-month General Assembly.

Senate Bill 1 was the first piece of legislation to be introduced this session. It passed the House on a 36-29 party-line vote.

With significant changes made in the House to the transportation funding bill, it still must pass the Senate or get out of a compromise committee and pass both chambers before midnight Wednesday.

Blessed by Senate President Kevin Grantham, a Republican, the Senate is expected to concur with the House and send the bill to the governor. In a session full of surprises … well, stay tuned.

After the legislature puts in $645 million into transportation the next two years, the state could borrow $2.35 billion for roads, bridges and transit, then pay it back with about $122 million annually.

That represents an infusion of about $50 million a year that isn’t already somewhere in the state transportation budget.

For the next two years, the state highway fund would get 70 percent of the money, while local governments and alternative transportation would receive 15 percent each. After the legislature borrows money, 85 percent would go to the state projects, and 15 percent would go to transit and other multi-modal projects.

Senate Republicans and other transportation advocates wanted a $3.5 billion bond issue for major highway projects paid by with $250 million annually from the state budget.

The bill also now includes a reserve that would keep the state from having to tap the budgets of schools or other services and programs when the state runs into an economic downturn.

“We are trying to balance competing needs so that we do not mortgage our future away and balance the budget in future years on the backs of students,” House Speaker Crisanta Duran, D-Denver, said in a statement before Tuesday morning’s vote on SB 1.

The Colorado Motor Carriers Association and others don’t like the possibility of “express lanes” with a toll to help pay for roads. They think such lanes unfairly benefit those who choose to pay to use the so-called “Lexus lanes” provided by all taxpayers.

The bill now includes a study of the tolling issue, which removes the complication from the funding measure.

On Monday, Democrats agreed to raise transportation fees on electric vehicles, since they don’t pay gas taxes to support transportation. On Tuesday, Rep. Faith Winter, D-Westminster, who chairs the House Transportation Committee, passed an amendment to remove the requirement, after hearing from the environmental advocates.

She said the fees on electric vehicles and autonomous vehicles is a bigger issue that should be considered later as the industry matures. Before it was amended Tuesday, the registration fee would have increased from $50 to $100, but was amended out on a 35-30 vote.

“We will continue this conversation,” she said.

Rep. Lori Saine, R-Firestone, said those who own electric vehicles who are among the wealthiest in Colorado.

“They can afford to pay an increase in registration to start paying their own way on our roads and bridges,” she said.