If Castle is indeed defeated Tuesday night it will be yet another sign that conservatives have a strangle hold on the Republican Party and moderates may or may not be welcome anymore. Castle has an overwhelming 69-21 lead with moderate voters but they only make up 33% of the likely primary electorate. O’Donnell has a 62-31 lead with conservatives that’s more than enough to propel her to the overall lead.

It’s clear that Castle’s popularity has taken a sharp turn in the wrong direction over the last month. An August PPP poll found his favorability with Delaware Republicans at a 60/25 spread. Now his favorables within the party are negative at 43/47. That’s largely a product of 55% of voters in his party saying they think he’s too liberal compared to 37% who think he’s about right.