With the February shooting of an unarmed Florida teen turning into a national controversy, top Democrats in Washington have begun subtly opening the door to new gun control policies, setting up a possible campaign issue for the 2012 elections.

So-called "Stand Your Ground" laws across the country have come under scrutiny in recent weeks after neighborhood watchman George Zimmerman gunned down 17-year-old Trayvon Martin. Florida became the first state to pass a "Stand Your Ground" law in 2005, expanding self-defense zones to most public places. As The Christian Science Monitor noted, the law does away with the English Law concept of a “duty to retreat.”

Even after the shooting of Democratic Arizona Congresswoman Gabrielle Giffords last year, Democratic leaders -- including President Barack Obama -- were virtually silent on new gun control legislation, but that has all changed in recent weeks as several top Democrats have suggested that it's time re-examine the ever-expanding gun culture.

The National Rifle Association (NRA), which lobbied Florida lawmakers in 2004 to pass the measure, has largely been silent on the controversy since Martin's shooting, but that could all change as the pro-gun group works to defeat Obama in November. "The law should not be on trial," NRA lead lobbyist Marion Hammer told The News Service of Florida last week. "The law did not do anything wrong." Calls to the NRA were not returned by the time of publication.

1 - President Barack Obama

At a White House event announcing the nomination of Dartmouth College president Jim Yong Kim to head the World Bank last month, the president called for every aspect of the Martin case to be investigated, including laws that make it legal to use deadly force without first retreating.

"I think all of us have to do some soul-searching to figure out how does something like this happen," Obama said. "And that means that examine the laws and the context for what happened, as well as the specifics of the incident."

2 - Vice President Joe Biden

Vice President Joe Biden said on Sunday that he expected a fresh debate over Florida’s “State Your Ground" law.

"I’m confident that the people of Florida will debate and discuss whether or not this law, that ‘Stand Your Ground’ law, whether it’s being applied as it was intended to apply, and whether or not as intended it makes sense," he told CBS host Bob Schieffer.

3 - Sen. Chuck Schumer (D-NY)

In an interview on CBS last week, Senate Judiciary Committee Chuck Schumer called on the Justice Department to expand their investigation into the Martin shooting to include "Stand Your Ground" laws.

"I'm sending a letter to the Justice Department today to ask them to expand their investigation into the general application of these Stand Your Ground laws, whether they actually increase rather than decrease violence and whether they actually prevent law enforcement from prosecuting cases where a real crime has been committed," Schumer said during an interview on CBS.

He also suggested that he would like to see congressional hearings on the matter.

"I think we should examine this law. They're all new," Schumer explained. "They've been passed very, very quickly. I think the states who pass them, if they find out the real facts, may decide to repeal them."

4 - Former President Bill Clinton

Speaking to ABC's Jake Tapper over the weekend, the nation's 42nd president also said it was time for a "reappraisal" of "Stand Your Ground" legislation.

"I think the law is going to create real problems because anyone can — anyone who doesn’t have a criminal background, anyone not prohibited by the Brady Bill and caught by the checks — can basically be a part of a neighborhood watch where they have a concealed weapon whether they had proper law enforcement training or not," Clinton observed.

"So I hope this will lead to a reappraisal of the Stand Your Ground laws," he said. "And I hope that the truth will come out and that the tragedy of this young man’s loss will not be in vain- it’s just terrible. ... The American people should re-examine their position on that and ask: Is this really worth it? Are we really all that much safer taking the chance that this kind of thing could happen over and over and over again?"

5 - Congressional Black Caucus leaders

Several Democratic members of the Congressional Black Caucus (CBC) introduced legislation last week that encourages the repeal of "Stand Your Ground" laws.

CBC Chairman Emanuel Cleaver (D-MO) and Florida Reps. Corrine Brown, Alcee Hastings and Frederica Wilson are sponsoring a non-binding resolution that "condemns unfounded reliance on Stand Your Ground laws to protect actions that extend far beyond historical use of self-defense … [and] urges any State legislature considering Stand Your Ground legislation to reject such proposals."