My personal opinion of why Henry Clay supported John Quincy Adams: 1- Crawford suffered a massive stroke during the campaign. In Clay's eyes, that makes him unable to perform the duties of the office of President. 2- Jackson was seen as a potentially as his strongest opponent in the next election, especially in the West. 3- Clay sèes Adams as the closest to him,amongst his rivals, in terms of ideology. (There might be a "corrupt bargain" between the two of them. The bargain would set a precedent where future Presidents would place formal rivals as their Secretaries of State [and potential successors], such as the duo of Polk and Buchanan..or Lincoln and Seward..or Obama and Clinton.)
My personal opinion of why Henry Clay supported John Quincy Adams:
1- Crawford suffered a massive stroke during the campaign. In Clay's eyes, that makes him unable to perform the duties of the office of President.
2- Jackson was seen as a potentially as his strongest opponent in the next election, especially in the West.
3- Clay sèes Adams as the closest to him,amongst his rivals, in terms of ideology.
(There might be a "corrupt bargain" between the two of them. The bargain would set a precedent where future Presidents would place formal rivals as their Secretaries of State [and potential successors], such as the duo of Polk and Buchanan..or Lincoln and Seward..or Obama and Clinton.)