Regarding Retake GMAT with 1 month time for R2 deadlines

Dear all

Needed some suggestions for the following.

I had taken GMAT on 1st Nov and scored paltry 680 (considering i am an Indian). Planning to retake GMAT on 6th Dec and targetting 730ish time time. The 3 b schools i.e. Stanford, wharton, and chicago have their R2 deadlines between 3-9 jan 2012 (i.e. about 30 odd days from the GMAT). Now assuming that i score 730ish which im confident , i am not sure if 1 month of time is enough to apply to 3 top b schools where the competition is already intense. in terms of app. prep, i have just done up with my resume and have started scouting for LORs and transcripts.
Do you think post GMAT, 1 month of application time i should reserve ONLY for 1 of these 3 colleges to have a good shot this season and NOT attempt to apply to all 3 of them and hence cramming my efforts in 1 month thereby diluting my application for all 3 ?

My Profile:

Undergraduation - among top 3 students
Graduation - Top 20 college in india ; 1st rank in the college
Post-grad MBA from a top 10 b school in india - Allrounder award
Work experience -
1. Big credit rating agency in india (2 yrs)
2. Associate at a domestic PE firm (1.5 yrs)
3. Software consulting at a global IT major (1 yrs)

Other activities - decent activities at school and college level
Currently teach CFA at a leading firm (part-time)
Some charity work in the past though not very active presently

Planning to remain in the same industry but want to target international PE firms which surely need better exposure and a good international b school education in india

Regards
Rohit