The National Labor Relations Board is expected to release a flurry of pro-labor decisions by mid-December, when Democrats could lose their majority on the federal agency.

The term of one of the board’s five members, Nancy Schiffer, expires Dec. 16, and the Senate has yet to confirm President Obama’s replacement nominee. If one isn’t in place before the end of the year, the White House will have to get one approved in the upcoming Republican-controlled Congress.

Many GOP senators think the board has tilted heavily pro-labor under Obama and would just as soon leave the spot vacant. Without a replacement, the board will have two Democrat and two Republican appointees and will likely deadlock on controversial cases.

“I wouldn’t be surprised if the NLRB tried to rush some decisions through before year-end if it can,” said Jim Jeffries, Republican spokesman for the Senate Health, Education, Labor and Pensions Committee.

Business groups are bracing for the decisions, which could include the timing of union elections, the use of company email, franchising rules and whether scholarship athletes are college employees.

Getting Senate confirmation ordinarily wouldn’t be difficult for the administration, since Majority Leader Harry Reid, D-Nev., has restricted use of the filibuster on nominations. But the lame-duck session is the Democrats’ last chance to push it through, and time is rapidly running out to schedule a vote.

Obama was so concerned about potential problems that he pulled his original nominee to replace Schiffer, former recess appointee Sharon Block, after Republican senators objected to her. Block was replaced last week by Democratic Senate staffer Lauren McFerran, who will now need an expedited confirmation.

Most expect that Reid will get a nominee confirmed before time runs out, but the situation gives the board an incentive to quickly complete any unfinished business.

No one knows for certain what the board will do, however. While the NLRB is a federal agency, it acts independently and doesn’t publicly schedule announcements.

James Sherk, senior labor policy analyst at the Heritage Foundation, said the NLRB’s biggest priority appears to be a rulemaking on speeding up union elections. “I would be very surprised if they don’t hand that one down before the end of the year.”

Currently, a workplace union election is supposed to take place 42 days after an NLRB regional director approves it. The new rule would speed up the process, allowing elections as little as two weeks after approval.

Unions have long sought the change because businesses often use the interim period to mount campaigns to convince their employees not to form a union. Time is a major factor in the outcome of union elections.

A Bloomberg News analysis found that unions win 87 percent of elections if they are held within two weeks of the NLRB approving one, but only 58 percent of elections when they take place after five or six weeks.

The NLRB tried to issue the rule in late 2011. The following year a federal court threw it out, saying the NLRB lacked a proper quorum when it adopted the rule. The board started the process over in February.

Businesses also are looking closely for signs of a potential new policy for determining when two businesses can be declared “joint employers” and therefore both legally liable in employment cases. The NLRB has strongly indicated it thinks the law should be overhauled in this area, which would have a major impact on corporations that franchise their brand names.

“We expect a decision … before the end of the year, probably before Dec. 16,” said Matt Haller, spokesman for the International Franchise Association.

In May, the board invited legal briefs in a case involving Browning-Ferris Industries and a decades-old precedent setting narrow criteria for determining when two businesses are considered joint employers.

NLRB General Counsel Richard Griffin Jr., a former top lawyer with the International Union of Operating Engineers, argued in a June brief that a much broader “totality of circumstances” standard should be used. Griffin illustrated what he meant a month later in a case involving worker complaints against McDonald's franchises when he instructed his lawyers to treat McDonald’s Corp. as the workers’ employer, not just the local restaurants where they work.

The announcement shocked the business community because most franchisees are understood to be legally separate entities from the parent company. McDonald’s says 80 percent of its estimated 3,000 U.S. restaurants are really privately owned businesses.

The NLRB told Bloomberg in late October that Griffin would release a memo explaining his legal reasoning in the McDonald’s case before the end of the year, but the case is not likely to be decided soon since it hasn’t officially gone before the board yet.

But the Browning-Ferris decision may be announced soon, Haller said.

Joshua Parkhurst, co-chairman of the labor law practice group for the National Employment Lawyers Association, agreed. “It’s a good one to look out for because it will give you a good idea of where the McDonald’s case is heading.”

Another potential NLRB ruling involves whether employees can use company email accounts for union organizing. Businesses have argued that if the system’s servers are owned by the company they ought to be able to forbid such use, pointing to a long-standing NLRB precedent governing use of company property.

Griffin disagreed, arguing in a brief for the case that the employees “have a statutory right” to use company email accounts so long as it is not during work hours.

The board also could issue a ruling in a high-profile case involving Northwestern University athletes. Union organizers say they are really employees of the school, not students, and therefore eligible to unionize. The case could have a major impact on college athletics.

The athletes voted on unionization in April but the ballots were impounded by the NLRB pending the board’s decision on the university’s appeal of the case.