With the withdrawal this week of Erroll Southers, President Obama's nominee to head the Transportation Security Administration, the question becomes: Will anyone be able to win Senate approval for that job?

Southers — a former FBI agent, and the assistant chief of homeland security and intelligence with the Los Angeles World Airports police department — was nominated in September and praised as well-qualified by many members of Congress. But his nomination languished for months after Sen. Jim DeMint, R-S.C., placed a hold on it. DeMint said feared Southers would allow TSA employees to unionize.

In an interview with Federal Times, Southers said he never endorsed unionization for TSA employees — he said only that he would study the issue. He predicts Obama's next TSA nominee will also fall victim to a process "held hostage" by DeMint.

"The only alternative is to nominate someone who absolutely refuses to allow [unionization]," Southers said. "And that nominee would be going against what then-Senator Obama said in 2008, when he said allowing TSA employees to unionize would be a priority for his administration."

Union leaders — who supported Southers, in part because of his openness to unionization — said they were disappointed to see his nomination stall.

"I am disappointed with the withdrawal of Erroll Southers," said Colleen Kelley, president of the National Treasury Employees Union. "It was clear from the beginning that Southers was extremely well-qualified for this critical homeland security post. Two Senate committees agreed."

John Gage, president of the American Federation of Government Employees, urged the administration to quickly appoint a new TSA administrator. But Gage said Obama could allow TSA employees to unionize even before an administrator is confirmed.

And Gage swatted away criticism — from DeMint and several other Republican legislators — that allowing TSA employees to unionize would hurt national security.

"The burden's on them — it's not on us — to justify why employees can exercise their constitutional rights to be a member of a union," Gage said. "Those who somehow just assume that being a union member compromises national security, they're the ones who need to put up or shut up. The explanations they've given so far are just fantasies."

Southers agreed, pointing out that many law enforcement agencies have unions.

"I don't know of any law enforcement agency that is unionized that has a problem operating," he said. "The Los Angeles Airport police department has six unions. We don't have a problem, and our airport is a prime target for terrorists."

DeMint's office did not respond to a request for comment.