The evidence suggests that he's to blame, but let's be careful not to 'jump to conclusions'. He may have a good explanation for what happened.
At this point, his victory seems to be a 'foregone conclusion'. [=his victory seems certain; there seems to be no doubt that he will win]
Most people felt that the outcome of the trial was a 'foregone conclusion'. [=they felt sure that the trial would end in a certain way]
(..) it's the scientific breakthrough of the afternoon. It's not true! Don't worry, I wasn't about to look foolish by jumping to conclusions, so I've sent an e-mail out asking everyone's opinions. Right. Well, that's a good idea. No, sorry. Could you run that part to me again? (..)2006 TvShow: The IT Crowd Title: Aunt Irma Visits Season: 1 Episode 6