Among the issues, which DeFazio called "deficiencies that were concessions to the Republicans," were provisions to weaken environmental regulations Republicans argued were delaying construction projects.
Democrats were also opposed to the lack of a Buy America provision that they had sought throughout the contentious negotiations on the highway bill, DeFazio said.
DeFazio acknowledged the protest from minority Democrats on the House Transportation Committee would be unlikely to prevent Republicans from bringing it to the floor of the House. A vote is expected to come as early as Friday, despite a House rule requiring legislation to be available for review for three days prior to the vote.
"The Republicans can bring it to the floor. They got enough signatures," he said.
DeFazio said he would likely vote for the final passage of the transportation funding bill despite his protest about the conference committee process that led to it.