Since July almost six hundred LDS Church members have expressed their disapproval and/or resigned.

Mormons Losing Members Over Anti-Gay Campaign

While the Mormon Church hierarchy was responsible for organizing millions of dollars and thousands of hours of manpower to pass California's Proposition 8 and Arizona's Prop 102, the church's tactics haven't sat so well with some of its members--including families, members with Mormon heritage going back 150 years, and gay members---who began speaking out in July on the website signingforsomething.org.
Many have public resigned from the church, citing reasons like these:
*I think the church has no right to assume the inner thinkings of its members and take such an open stand of any political issue.