Stephen Bannon has said there is a "special place in hell" for Republicans who failed to show support for Roy Moore.
Donald Trump's former right-hand man was speaking at a campaign rally for the Alabama senate seat candidate on Monday.
In the speech, he blasted Senate Majority Leader Mitch McConnell, Alabama senator Richard Selby, and former secretary of state Condoleezza Rice for failing to show support for Moore, who has been accused of sexual misconduct towards a minor.
He told crowds at the rally there was a "special place in hell" for Republicans who "should have known better."
Several members of the party called for Moore to pull out of the race after a number of women came forward with allegations of unwanted sexual advances.
The candidate has vehemently denied the claims, saying they were lies.
Moore's heated race against Democratic candidate Doug Jones for the state seat is due to conclude this week.