The Senate voted 55-44 Tuesday to confirm President Obama’s nomination of Richard Griffin to serve as general counsel to the National Labor Relations Board (NLRB).

The vote came just hours after cloture was invoked because eight Republicans joined Democrats to advance the nomination. Sen. Lisa Murkowski (R-Alaska) was the only Republican to vote for Griffin's final confirmation.

Some Republicans criticized Griffin for being a former labor union advocate. But Senate Health, Education, Labor and Pensions Committee Chairman Tom HarkinThomas (Tom) Richard HarkinDem Senator open to bid from the left in 2020 Senate GOP rejects Trump’s call to go big on gun legislation Trump should require federal contractors to follow the law MORE (D-Iowa) said Griffin deserved a “strong bipartisan vote” because of his legal experience defending unions and his prior service on the NLRB.

“I have no doubt that he’ll do an outstanding job,” Harkin said. “Why do my Republican colleagues have so much trouble voting for someone who was a lawyer for labor unions?”

Griffin’s nomination was controversial because earlier this year the Federal Appeals Court in Washington, D.C., found that Obama unconstitutionally appointed Griffin when Congress wasn’t officially recessed in 2012. The Supreme Court is expected to review that decision. 

In July, Senate Republicans allowed votes on five other NLRB members in order to keep the board operational. But that agreement came only after Obama withdrew the nomination of Griffin and replaced him with someone else.

AFL-CIO President Richard Trumka praised the Senate's action.

"With today’s confirmation of Richard Griffin to serve as General Counsel, the NLRB is now running on all cylinders to meet its duty to fairly and impartially oversee the workplace rights of millions of Americans," Trumka said. "

Senate Majority Leader Harry Reid (D-Nev.) said GOP obstruction has created a “backlog” of Obama nominees and vowed that the Senate would continue to work through some “critical” executive branch nominees this week, including for key posts such as directors of the Office of Personnel Management, the Federal Housing Finance Agency and the Federal Communications Commission.

This article was updated at 6 p.m.