Democrats have one goal in 2018: win the House back. But California's 39th district is a case study in what can go wrong when the national party gets involved in local races.
The Democratic divide: The DCCC backs Gil Cisneros, one of six Democratic candidates. The California Teachers Association (the state's largest teachers union with 325,000 members who've spent millions on races in the past) announced its support for Mai Khanh Tran today. And the Bernie Sanders-aligned Our Revolution PAC backs Andy Thorburn.