There’s been precious little polling of the Republican primary in Delaware, because longtime Rep. Mike Castle was thought to have no problem in his race against perennial candidate Christine O’Donnell. Castle has represented Delaware as Governor and Congressman for 30 years, and given that he represents the best (maybe only) chance for Delaware to pick up a Senate seat, you would think that primary voters would take that into account and excuse his occasional steps off the conservative reservation. But the momentum for O’Donnell began a few weeks ago, and the only poll out there now shows her with a slight lead.

It looks like there’s a real possibility of a major upset in the Delaware
Senate primary on Tuesday night, with insurgent conservative Christine O’Donnell
leading longtime Congressman and Governor Mike Castle 47-44. That 3 point lead is
well within the poll’s margin of error.

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.

You can buttress this poll with the actions of Castle and the Republican establishment in Delaware, who have all-out attacked O’Donnell (who has much in her past that’s attackable) in the past two weeks. Based on these numbers, it doesn’t seem to be working.

This sets up nicely for Chris Coons. Only 50% of Republican primary voters think O’Donnell is fit to hold public office. The tight race in Delaware seems more like a message from the conservative base to that rare species, the moderate Republican, that they are no longer welcome in the party. In a general election, O’Donnell polls behind Coons by double digits, while Coons trails Castle by the same.

Apparently, Castle could bolt the GOP and run as a third-party candidate, but only as a write-in; the deadline for an independent bid on the ballot has passed. Significantly, O’Donnell has run as a write-in candidate after losing a US Senate primary in 2006, and given her attitude I would see no reason why she wouldn’t again, cleaving off a slice of the conservative vote and helping Coons immensely. I think the race could lean Coons regardless of tomorrow’s outcome, in this scenario.

Some progressive commentators lament this outcome, because the inhospitability of the GOP to anything not rigidly conservative shifts the debate to the right and harms progressive causes. That may or may not be true, but the fact is that ship has sailed long ago. Olympia Snowe and maybe Susan Collins have no shot for re-election, and after that, the Senate will be almost perfectly ideologically pure. In New Hampshire, establishment Senate candidate and Attorney General Kelly Ayotte is barely hanging on in her primary, also tomorrow, and the one more moderate candidate, businessman Bill Binnie, not only is far behind, but has received death threats for his pro-choice stance. The question of moderation in the GOP basically has become a dead conversation, and there’s no point in pining for it. Conservatives have won their battle for the soul of the Republican Party; it’s time to deal with that reality.