Mike Castle has double digit leads over former Lieutenant Governor John Carney and New Castle County Executive Chris Coons, two hypothetical 2010 opponents for his House seat.
It appears, however, that Carney would start out in decent position to give Castle the strongest challenge he's had in years. Castle is actually below the magic 50% considered safe territory for incumbents, with a 49-32 edge over Carney. It's a wider 56-21 edge over Coons.
Carney and Coons are each unknown quantities to a large swath of state voters, giving either a lot of room to move up if they decided to make the race next year. While all but 13% of Delaware voters have an opinion about Castle, 35% are ambivalent toward Carney and 45% have no feelings one way or the other about Coons.
Among those who do know them, Carney gets a positive 37/28 rating and Coons' is 30/25.
Carney, who seems the more likely of the two candidates, is under performing with Democrats and several key demographics that tend to support the party's candidates. For instance he has just a 48-34 advantage with voters in his own party, and also is at 48% with black voters and only 24% with those under 30. Those numbers would all likely improve a good deal if he made the race.
Certainly Castle's numbers are strong and he would be heavily favored against either of these challengers. But these numbers do not show invincibility- in fact Elizabeth Dole held a 17 point lead in our polling on the North Carolina Senate race last year as late as February even after challengers to her had been campaigning for several months. This could be a race to watch if Carney makes it.
Full results here.