The White House on Friday refused to float possible successors to outgoing Homeland Security Secretary Janet Napolitano, but a handful of candidates are receiving buzz in the wake of the shakeup to Obama’s second-term Cabinet.

Formed in the aftermath of the Sept. 11 terrorist attacks, the Department of Homeland Security is one of the most complex and massive federal agencies, overseeing issues ranging from border security to terrorism and natural disasters. In tapping Napolitano, the former governor of Arizona, Obama made a similar choice to President George W. Bush, who also picked a chief executive for the post: former Pennsylvania Republican Gov. Tom Ridge.

However, multiple administration sources pointed to possible candidates within DHS who likely would face little resistance on Capitol Hill. Craig Fugate, administrator of the Federal Emergency Management Agency, is believed to be in the running for the post. So is John Pistole, administrator of the Transportation Security Agency, who has deep ties with lawmakers from both parties.

“I think both of those would be safe choices,” one administration official told the Washington Examiner. “If [Obama] doesn’t want a fight with Congress, either of those choices would make sense.”

The chief position at DHS is among the most high-profile posts in the Obama administration, particularly with the immigration debate coming to a head in Washington. Napolitano, who will stay on until September, has been Obama’s key defender in combating GOP charges that the administration is not doing enough to secure the border.

And it didn’t take long for others in Washington to weigh in on Obama’s choice.

Sen. Chuck Schumer, D-N.Y., called White House chief of staff Denis McDonough to recommend New York City police commissioner Ray Kelly for the job.

“The Department of Homeland Security is one of the most important agencies in the federal government,” Schumer said. “It’s leader needs to be someone who knows law enforcement, understands anti-terrorism efforts, and is a top-notch administrator, and at the NYPD, Ray Kelly has proven that he excels in all three.”

Massachusetts Gov. Deval Patrick also has emerged as a potential frontrunner for the position. However, Patrick, a close ally of Obama’s, has expressed more interest in potentially replacing Attorney General Eric Holder one day.

Obama has consistently reached across party lines to fill national security posts, as he did recently when he nominated James Comey, a registered Republican, as his next FBI director.

In that mold, Rep. Gerry Connolly, D-Va., vouched for Sen. Susan Collins, R-Maine, as a possible replacement for Napolitano. Doing so also would open up a competitive Senate seat for Democrats.

Regardless, the next DHS secretary will replace one of the most experienced members of Obama’s team.

Just five Cabinet members have been with Obama since he took office in 2009: Holder, Health and Human Services Secretary Kathleen Sebelius, Secretary of Education Arne Duncan, Secretary of Housing and Urban Development Shaun Donovan and Secretary of Veterans Affairs Eric Shinseki.