Excerpts from the LA Times

But the demonstrations also have raised questions about whether the in-your-face approach will alienate voters, who may be asked one day to approve gay marriage. Twice in the last eight years, voters have rejected it.

"I think the No on 8 forces have devolved into mob justice," said Jeff Flint of Southern California
Several opponents of Prop 8 have already begun to apologize publicly to their friends who supported prop 8.
..."I find this backlash disgusting and shameful and I fear that it makes gay-marriage advocates seem aggressive and intolerant. We just spent 4 months and $40 million in an effort to convince California voters that gay-marriage won't lead to an attack on the religious liberties of churches who do not condone gay marriage. Now our actions are really convincing the people that our quest for equality will indeed clash with religious freedoms. The public rarely empathizes with an aggressor and these protests targeting businesses and churches are staining our image as the "under-dog in need of compassion", said one worker with the No on 8 campaign. "We need to stick to public demonstrations that do not attack individuals and groups. I was appalled to hear from my neighbors who donated to the Yes on 8 campaign that they were approached and threatened by strangers carrying lists of donors. "Extortionists" is the last thing we want to be called, especially when the fate of our marriages lies in the hands of the public. Here we are, advocating that we be treated fairly while groups of passionate youth treat our opponents unfairly. It just isn't going to work."
...Michael Weinstein, president of the Los Angeles-based AIDS Healthcare Foundation, called for a thorough analysis of the failures of the No on 8 campaign. He said, "We need to show we can win in the court of public opinion."
...Whether the current protests will help or hinder that effort remains unclear, said Bruce Cain, a political science professor at UC Berkeley.

"It can backfire," he said.

"The key, he said, is that the protesters not irritate or alienate the people they are trying to persuade by appearing too out of the mainstream or by tying up traffic for hours."