Lemme address the Jeremy Corbyn-Bernie stuff Nap posted. Bernie could lose of course if he's the nominee because he's not as strong of a general election candidate as he was in 2016, Republicans are unified, the FBI is gonna meddle again and I think Dem resistance has been mostly a joke.
Corbyn is the man but Bernie has a lot of strengths that Corbyn didn't have. Bernie is a way better politician than Jeremy. Way more competent. Bernie has more evidence of being pragmatic and firm in his views. The global electorate is punishing candidates if they get the feeling that they're not being honest about their positions.
You saw this happen at the debates where Boris Johnson hammered Corbyn at the debates multiple times saying, "What's your position on Brexit?" and Jeremy wouldn't answer the question...until the fourth time where he said that he would remain neutral in a second referendum. He looked weak.
People keeping bringing up how Bernie's comments about Castro and the Sandernistas will hurt him similarly to Corbyn and the IRA/Hamas... I don't think this will matter. Bernie knows how to deflect. Also America needs radical economic change more than the UK and Bernie has swing voter appeal while Corbyn's appeal was narrower. The UK conservative party is more friendly to social programs than the republicans are.