Sarah Palin and the others on the right who used intimidation and violent speech will not apologize for it. They won't even mention it. If they don't mention it, it doesn't exist and therefore they did nothing wrong. If pushed about being responsible for creating a climate of violence and hate, they'll blame the shooter saying that he's the lunatic, it's all his fault. How could they possibly have any responsibility for the actions of a madman? The left will clamor about it for a while but nothing will actually get done about it and most folks will forget about it after a while.
Commentators and politicians on both sides will avoid violent imagery for about a month. After that, first folks on the far fringes will start it up again and then it will gradually move more mainstream. If called on it, they'll say that of course they didn't mean it like that.
President Obama will neglect the opportunity to say that he's been asking for people to tone down the rhetoric and vitriol for some time and now he's renewing that same call. Despite this being a chance to get folks to actually do their jobs and talk to each other (even if only for a little while), partisanship will continue on without a hiccup other than in photo-op newsbites saying "of course we're horrified by this".