Castle didn’t switch in 2007 because it wasn’t advantageous of him to do so. Had it benefitted the Democrats, perhaps, but joining a party already in the majority with comfortable numbers would not have gained him anything. They certainly wouldn’t have handed him a chairmanship. It’s also unlikely he could’ve won the primary for the Senate seat, since Democrats are often unforgiving of someone switching over from the GOP. As left-wing as he is, it wouldn’t be enough. Hell, to CT Democrats, the almost 100% perfect left-wing Joe Lieberman wasn’t pure enough.
I’m quite glad Conservative Bill Roth didn’t step down in 1994 in favor of left-leaning Castle. Assuming he’d have won that year, a Sen. Castle would not have won reelection in 2000 as a Republican against then-outgoing Gov. Tom Carper. Remember all the seats the GOP lost that year. Now, if he had won reelection, he might very well have pulled a Jeffords before Jeffords (or they might’ve jumped together). In any event, he’d still likely have been out by 2006 (again, losing the Dem primary, probably again to Carper).
Had the House seat come open in 1994, perhaps either Jane Brady (running for Attorney General) or Janet Rzewnicki, the State Treasurer, might’ve jumped in. But I believe both women would’ve had trouble in or after 2000. Rzewnicki actually ran against Castle in the 1992 primary for the open House seat, losing 56-30%. She scored a decisive 67% of the vote in 1994 for her 4th term as Treasurer. She was the logical choice to run for Governor in 1996, but only got a dreadful 31%. In 1998, it was a complete fiasco, as she lost her job as Treasurer to future Governor Jack Markell, getting just 42%. I expect had Rzewnicki won the House race in 1994, she would’ve lost reelection in 1996, and the Dems would’ve held it ever since. Jane Brady probably wouldn’t have fared much better. She managed to hold on to her job as late as the 2002 elections, but won with a bare plurality of just 48%, and she moved over to the Superior Court before her term expired in 2007, giving the Dems the office.
As for Pete duPont, he should’ve run against Plugs in 1984, in what would’ve been the marquee race of the year (or at least tying the Helms-Hunt race in NC). At least that cancer would’ve been excised long ago. duPont could’ve sat in the seat until at least 2003 without too much of a problem. I wouldn’t have suggested at 75 that he try to run in 2010 (then again, my almost 75-year old ex-Governor Bredesen is trying for a first term in the Senate).
That a “gadfly” like O’Donnell was able to beat Castle exposed just how out-of-touch and arrogant he was. I remember seeing part of a town hall meeting from around 2010. The sense of entitlement was off the charts. He was the epitome of the establishment politician and as grotesquely anti-Conservative as one could get. He got his just desserts for his actions in office, and the screwing he gave the DE GOP and the political base. That was entirely on him. It was the duty of Delaware Republicans to defeat him, and that was that. BTW, O’Donnell still got roughly the party base in the state, over 40% (almost what Trump got 6 years later). That was better than her 2008 performance against Plugs, which she improved upon from 35%. It even topped that of the aforementioned Jane Brady, when she ran against Plugs in 1990 and got just under 36%.
Again, performing at or above the average for a GOP Senate candidate didn’t make her a disaster. Add to that the RINO Establishment, Castle’s flunkies (who refused to endorse her after her victory), the national Dems and the media running a disgusting, sexist and slanderous campaign against her, she still did well.
Valid point, O'Donnell's numbers were decent compared to when the DE GOP got their way and ran RINO Jan Ting as the party nominee because they said he was the only "credible" and "electable" candidate. The party backed RINO Ting beat conservative outsider Mike Protack in the primary, then went on to get crushed in November, and couldn't even muster 30% of the vote statewide. He was basically Delaware's answer to Steve Sauerberg. Ting went on to endorse Obama and was then forcefully expelled from the GOP and officially joined the RAT party. He won't be missed.