That's better.
-CPU wise, while the power pc cpu is clocked higher, it is not much better than the 3DS cpu capabilities. The 3DS has 2 cores, 2 auxiliarry vector units, and a 3rd ARM9 cpu for sound and IIRC some other tasks. Depends on the code, but it is not a big difference, and it doesn't matter so much for video games anyway, the gpu is the stuff that really makes or brakes the ability to play games
-Ram wise, there is no contest, really. I mean, really. 43mb RAM non unified ram vs 128, no contest here. And although for a Twilight port more ram wouldn't normally do much good, good devs could probably exploit it with smart tricks to give the 3ds an edge...
-GPU wise, the Gamecube and the 3ds are about in the same league. In raw power the Flipper is somewhat better, BUT the PICA is more advanced in terms of architecture and effects, and it has a smaller output target, so it doesn't need to have the same power. The 3DS needs to display 400x240, while the Gamecube was 480p. 4 times less pixels people...
Also, the game medium is better for the 3DS, so again devs could use "creative tricks" to give an edge to the 3ds port, while on the gamecube, much of the coding tried to overcome the limits of disk access and low general purpose ram...
There is no doubt a Twilight princess port is possible on the original 3ds handheld.
But of course Nintendo will say "it is only possible on the New 3DS", and millions of lemmings will buy that...