GameBoy Advance vs PSP? Would GB still win?

[PS360N64PSXBOX]

Now the DS and PSP launched in 2004, I think Nintendo lauched the DS to compete with the PSP and give them an edge. But I was wondering, if Nintendo had stuck with the GameBoy advance or had Sony got the PSP to go head to head with the GBA would Nintendo still had won or would the PSP been able to overtake it on a month by month basis? The DS has a gimmick to aid it,but the GBA did not, No dualscreen or anything.

 My basic question is would the GBA have done as well against the PSP as the DS is?