Yes, of course they are related. Everyone who has a last name with Jackson is related. Everyone knows that! That is jus common sense! Like everyone with Smith is related too! 
Here are the earliest Jackson's that we know of... 
1582 – Richard Jackson b. 1582 England came to Conn. c1630 
1605 – Robert Jackson 1605 – 1681 Hempstead, Long Island, New York 
1645 – John Jackson b. abt 1645 VA 
1650 – Ralph Jackson b. 1650 England d. 1708-1709 England 
1675 – James & Rebecca Hallett Jackson circa (1675-1735 NY) 
1713 – John Jackson died within the Colony of Virginia 
1719 – Benjamin Jackson Sr. b. 1719 Queens Co.,d.abt 1805 SC 
1730 – Samuel Jackson b. 1730 Chester County, Pennsylvania 
1730 – Richard Jackson b. circa 1730 England 
1730 – Thomas Jackson, Sr. b. circa 1730 
1737 – William Jackson b. 1737 N. Ireland d.1792 in Guilford Co., NC 
1745 – Ambrose Jackson b. Colony of VA d. 1745 Brunswick Co., Colony of VA 
1758 – Churchwell Jackson b. 1758 VA d. aft 1858 Marion Co., TN 
1761 – Richard Jackson b. 1761 (place unknown) d. Barnstable Co, Mass.