Now that President Obama has formally unveiled his proposals to curb gun violence -- banning high capacity ammunition clips, a ban on assault weapons and universal background checks -- the fight now moves to Congress.

And, that is where the idealism of these proposals will run into hard, practical realities. None is more concrete than the influence the National Rifle Association exerts in House and Senate -- thanks in large part to its ability to spend significant sums to help Members of Congress get elected.

Below -- thanks to WaPo graphics wizard (and North Carolina Tar Heels fan) Wilson Andrews -- the story of the NRA's financial influence in Congress is told though a series of charts detailing the organization's political contributions during 2012. It's fascinating stuff.