The Fox News debate without front-runner Donald Trump attracted the second-smallest audience of the seven such televised encounters among Republicans so far this election cycle, according to early ratings figures released on Friday.

According to preliminary Nielsen data, 12.5 million people watched the Republican face-off, beating only an earlier debate on the less-prominent Fox Business Network.

Thursday's encounter still was one of Fox News' biggest-ever hits and drew more viewers than coverage of a rally that was hosted by Trump at the same time. The billionaire refused to participate in the debate out of anger that Fox News anchor Megyn Kelly was a moderator.