If we nominate a socialist... we will get 4 more years of what we saw tonight

[TexasTowelie]

111. But the odds are being made for each event being treated independently.

The odds on event A (receiving the nomination) at 39% for and 61% against. The odds for event B (winning the election) are 25% and 75% against winning.

Look at it from this perspective (and I haven't actually checked the odds for the GOP side):

Let's say that the odds are 95% for Trump to get the GOP nomination. Meanwhile, the odds of Trump winning the general election are at 50%. Does that mean that Trump has a [95/(95+50)] (66%) chance of winning? The answer would be no, because it contradicts the odds of Event B being 50%. And if we changed the odds of Trump winning the general election to 55%, then following your logic it would mean that Trump has a [95/(95+55)] (63%) chance of winning. This is another contradiction where even though there is an increase in the odds of winning (from 50% to 55%), he would end up with a lower chance of (from 66% to 63%) of winning.

The only dependency between Event A (the nomination) and Event B (winning the election) is that if event A isn't achieved, then Event B cannot occur (barring a third-party run).