http://www.rollcall.com/news/politics/fbi-searched-office-of-rep-duncan-hunters-campaign-treasurerHunter is the target of an ethics investigation by the DOJ regarding misuse of campaign funds.
CA-50 is an R+11 district, although the Clinton vs Trump margin was 9 points tighter than Obama vs Trump.
However, I think Democrats have a sliver of a chance, for a representative similar to how Joseph Cao won in 2008 in LA-02 after William Jefferson was indicted on corruption charges. Additionally, if the top-2 primary results in Dem vs Dem for both senate and governor, I think there'd be enough Republicans staying home for a potential flip.