President Obama has triggered a new fight with Republicans by re-nominating two controversial officials to key administration posts.

Obama on Wednesday re-nominated former labor lawyer Craig Becker to the National Labor Relations Board, and Donald Berwick to serve as administrator of the Centers for Medicare and Medicaid Services. 

Both are already serving those posts, as they were named as recess appointments in the last year. The moves show the White House is standing by its nominees despite Republican gains in Congress from the last election.

Republicans oppose their nominations, and have criticized the White House for once again nominating them. They would both seem to face tough odds to win approval from the Senate, where Republicans now control 47 seats.

Business groups say Becker, a former associate general counsel to both the Service Employees International Union (SEIU) and the AFL-CIO, is overly sympathetic to labor. Berwick, however, has widespread support from healthcare industry groups including the American Hospital Association and the American Medical Association, despite GOP accusations that he favors rationing patients' care.

Unions have supported Becker's nomination, saying he would add balance to a labor board that too often tilted toward business under the George W. Bush administration.

Josh Goldstein, an AFL-CIO spokesman, said Becker was "highly respected and qualified."

"Without a fully staffed [National Labor Relations Board], working families face a major disadvantage in winning justice in the workplace," Goldstein said. "Republicans will again have a chance to reject politics-as-usual and put the needs of American working families over their own political interests. Ball’s in their court now."

One of the groups that opposed Becker's nomination in 2009 says it plans to work to stop his confirmation again.

“In renominating Becker, President Obama has sent the message to employers across the country that his rhetoric is just that, and the nation’s chief executive is more concerned with paying back union bosses than turning the economy around. We will work with small-business owners to ensure the Senate once again rejects the Becker nomination in a bipartisan manner,” said Katie Gage, executive director of the Workforce Fairness Institute.