Grayson has been accused of domestic violence by his ex-wife.
This is the GOP senator's second key labor union endorsement in two days.
Democracy for America and the PCCC said they will no longer back his Senate run.
"I'm hoping that somebody comes here and arrests you," Rep. Alan Grayson told a Politico reporter.
Rep. Joaquín Castro said he'd consider a Senate bid in 2018.
Pennsylvania's Democratic nominee called her opponent an "a--hole."
Rep. Alan Grayson's attorney rejected the accusations.
The seven-figure buy targets Democrat Evan Bayh for his votes for the Wall Street bailout.
“Do national Democrats condone this type of language and name-calling?” the NRSC asked.
Melanie Zanona 07/25/16 06:01 PM EDT
The Ohio Teamsters had previously backed Ted Strickland, Portman's challenger, for governor.