3- 99% may be more of muslims accepted Khilafat of Abu Bakr ra.
This is a misstatement.
Hazrat Imam Ali (as) did not give allegience to the caliph. With him remained from the very beginning the most prominent and close companions, like Ammar ibn Yasir, Miqdad bin Aswad, Salman Farsi, Abu Ayub Ansari, Jabir bin Abdullah, Saad b Ubaydah, Banu Hashim the tribe of our Prophet (saww) and more who were all supporters of Hazrat Imam Ali (as).