Politicizing churches is a bad idea for lots of reasons. Not only it is illegal for non-profit organizations to endorse or oppose candidates, it also can divide congregations and lead to other types of problems.
Exhibit A is Cornerstone World Outreach, a church in Sioux City, Iowa. Last year, Cornerstone Pastor Cary K. Gordon decided to use his house of worship to launch an effort to recall three Iowa Supreme Court justices. Gordon was angry that the three, who faced retention elections, had voted to legalize same-sex marriage in the state.