and margaret warner gets an update on the violence, and the crackdown, on drug kingpins from nicholas casey of the "wall street journal" in mexico city. >> woodruff: plus, we have a second look at spencer michels' story behind the story of a surprising bestseller. >> mark twain decreed that his autobiography couldn't be published until 100 years after his death. that's this year. >> ifill: that's all ahead on tonight's "newshour." major funding for the pbs newshour has been provided by: >> i do a lot of different exercises, but, basically, i'm a runner. last year, i had a bum knee that needed surgery, but it got complicated because i had an old injury. so, i wanted a doctor who had done this before. and united healthcare's database helped me find a surgeon. you know, you can't have great legs, if you don't have good knees. >> we're 78,000 people looking out for 70 million americans. that's health in numbers. united healthcare. >> and by the bill and melinda gates foundation. dedicated to the idea that all people deserve the chance to live a healthy productive life. and with the ongoing supp