Obama Gun Control 2013 News: 100 Days After Sandy Hook Shooting, President Calls On Senate to Pass Bill

Over 100 days after the deadly shooting at Sandy Hook Elementary School in Newtown, Conn., support for new gun control measures is waning nationwide.

Before public sentiment swings away from restrictions on firearm purchases, President Obama is trying to push through measures to make it more difficult to obtain high-capacity and high-powered firearms.

He was joined by family members of the 20 schoolchildren and six staff members killed at Sandy Hook at a White House event on Thursday where he called on the Senate to pass gun control legislation in April.

"This is our best chance in more than a decade to take common-sense steps that will save lives. We have an obligation to try. There's absolutely no reason that we can't get this done," the president said.

"The entire country was shocked, and the entire country pledged we would do something about it and that that this time would be different. Shame on us if we've forgotten," he said.

Next month, the Senate will vote on whether to require background checks for firearms purchases, a measure supported by over 90 percent of the American public. That support crosses party lines, and typically pro-gun Republicans support background checks at a rate only about 2 points lower than Democrats and independents.

In addition, the bill also increases penalties for gun trafficking, in a move designed to reduce the number of illegally purchased handguns.

An assault weapons ban originally part of the proposal has been dropped, as has restrictions on high-capacity magazines, after Senate Majority Leader Harry Reid said he did not have enough votes to carry those measures. They will be introduced as amendments to the bill, but the likelihood of passage is low.

Support for general gun control measures has dropped recently, falling to 47 percent nationwide, down from a high of 57 percent after the Newtown shooting.

Opposition to new gun control regulations has been spearheaded by the National Rifle Association, the largest and most influential gun rights lobbying group in the country. Many politicians on both sides of the aisle are wary of angering its politically-active membership, fearful that they will face primary challenges from pro-gun candidates in upcoming elections if they vote to restrict firearms in any way.

The president called out the NRA in his remarks today.

"There are some powerful voices on the other side that are interested in running out the clock or changing the subject or drowning out the majority of the American people to prevent any of these reforms from happening at all. They're doing everything they can to make all our progress collapse under the weight of fear and frustration or their assumption is that people will just forget about it," Obama said.

Until the vote next month, the White House will continue to push back against the gun lobby, though success is by no means guaranteed.