No effect on the market. If anything, it will draw Democrats and Republicans closer together to condemn such acts of violence. The critically wounded Congresswoman was anti-illegal immigration. So, if the shooter (who was caught) turns out to be an illegal alien, the calls to secure the boarder will be deafening.
Odd that we just had another anti-government violence two days ago: "2 package bombs explode at government buildings in Maryland, causing minor injuries and evacuations" http://www.nydailynews.com/news/nat...ode_at_government_buildings_in_maryland_.html