This week was also expected to be a high profile testing ground for expanding the gun control advocacy agenda to include opposing "Stand Your Ground" laws, which some believe played a role in the death of teenager Trayvon Martin and the acquittal of the man who killed him, George Zimmerman.
A Senate hearing was initially planned to address Stand Your Ground laws today, but was postponed due to the tragedy at the Navy Yard, an irony in itself for many gun control advocates.
But the Newtown families had planned to make a powerful statement by sitting in the audience while Martin's mother Sabrina Fulton, who has become an advocate for repealing Stand Your Ground laws, testified before lawmakers.
"It was very important to our families," said Po Murray, a Newtown resident and vice chairman of Newtown Action Alliance whose four children went to Sandy Hook Elementary School. "Obviously we're very emotional at this time and we do think it's definitely an effort that we need to support."
Both the efforts to repeal Stand Your Ground Laws, which are supported by the NRA, and the efforts to strengthen background check legislation, which is opposed by the NRA, face long odds.
President Obama pushed aggressively in the wake of the Sandy Hook shooting for gun control legislation, but those efforts have slipped lower on his agenda in recent months, even while he has continued to pursue executive actions that don't need congressional approval.
And in the Senate, a second chance to pass background check legislation will likely only come if a new, significantly revamped bill is introduced that can garner new votes.
"There's hope among advocates to bring a bill up in the Senate, but there's a realization that you can't bring up the same bill because it's not going to get enough votes. Changes need to be made," said Jim Kessler co-founder of Third Way, a moderate Democratic think tank that advises gun control advocates. "If we're not going to at least make progress in terms of votes we don't just want to bring it up for a symbolic vote."
Though they acknowledge the difficulty of their task, there is real hope that the momentum has shifted in their favor.
"I would not be going back to Washington if I did not think we had a chance and we were going to get there," Wagner said.