elizabeth wilner, finally, if somebody says to you, "paid advertising is history," what do you say? >> oh, well, i can't laugh right now, but i would laugh. it's always effective at the margins, as ken has said,ing and in a close race treally does make a difference if it's done well. >> woodruff: because people who don't b see twitter and don't see the news media are going to be seeing other television and radio where these paid spots will be. >> that's right. and there will be a number of good portion of people in a close race at the end of the day who are not online looking for information, who are not following tweets, who are not necessarily watching the news, but they might be watching a baseball game or hockey game and they'll see an ad, and that might help change their mind or make up their mind. >> woodruff: that's what makes it all so hard to predict. >> yes.>> >> woodruff: elizabeth wilner, ken goldstein, we thank you.wi >> thanks. >> thank you. >> woodruff: next, a stinging report on police tactics in a city where civic tensions have been running high. john yang has our s