Union leaders said Majority Leader Mitch McConnell can't pick and choose which presidential election determines when to fill a Supreme Court vacancy.
President Obama named the board, at the request of the unions representing the railroad's 4,000 workers, on July 16.
"Dignity and opportunity aren't just gifts to be handed down by a generous government or by a generous employer. They are rights."
Union leaders gave President Obama's 2015 State of the Union address generally positive reviews.
Obama, for the first time since he took office six years ago, used his State of the Union Speech last Tuesday to call for new, tougher labor laws to protect worker's rights.
In one of the first signs he may be feeling pressure from the incoming Senate Republican majority, Obama officially dumped the nomination of Sharon Block.
Saying the Guatemalan government did not live up to its own worker rights commitments, the Obama administration will push its trade case against the Central American nation.
The Supreme Court ruled against the president and supporters in the labor movement by restricting the ability to fill vacant government positions before getting full Senate approval.
The president received ovation after ovation as he called for raising the minimum wage, with the greatest cheers coming when he described the increase as "common sense."
Gerard ran down a range of progressive initiatives Obama has proposed during his five years in the Oval Office. Then he launched his blast at the GOP.