The United States Senate on Wednesday voted down proposed restrictions to curb gun violence in the aftermath of the massacre at Sandy Hook Elementary School in December. Among the proposals defeated, a bipartisan plan to expand background checks to online and gun shows and a ban on rapid-fire  assault  weapons, like the one used in Newtown, Connecticut.    President Barack Obama called Wednesday, "a pretty shameful day for Washington," and the parents of Sandy Hook victims in Washington for the vote agreed. "Our hearts are broken, our spirit is not," said Mark Barden, father of Daniel Barden. Takeaway Washington Correspondent Todd Zwillich looks at the final political showdown and considers whether the NRA has won the gun debate-- and why.