The link below will take you to a brief article by The Huffington Post on the current status of the House Transportation Bill, and it sites several political reasons for the delay in the floor vote. It now appears Republicans will muster enough votes to bring the bill to the floor in late February. The article is particularly interesting if you like the financial details behind how amendments get offered and included in bills.
 
House Transportation Bill: Lobbying And Lawsuits Behind Move To Strip Worker Protections
 
Larry Innis
MRAA Legislative Affairs