From 1788–1792, the pro-slavery West Indies lobby (which included the Duke of Clarence, one of the sons of King George III) organised a fight back against the abolitionists.
The lobby was made up of individuals who owned plantations in the West Indies and those who profited from the slave trade in some other way, whether directly or indirectly. The West Indies lobby monitored abolitionist activities in newspapers and magazines. They then employed writers of their own to respond by circulating pro-slavery letters and articles in the same newspapers.
The lobby had questionable success. They were able to block abolitionist bills in Parliament because many MPs owned property connected with the slave trade.
However, the West Indies lobby was a minority motivated by financial gain, whereas the abolitionists had a strong moral cause which gradually turned into a popular movement. Often the abolitionists had such strong evidence against slavery (eg the Brookes diagram) which was harder to counter.
The French Revolution delayed the abolitionist campaign for several reasons:
A slave revolt on the French colony of Saint Domingue frightened the British government who thoughts steps towards abolition would encourage more slave rebellions. Led by Toussant L’ouverture the freed slaves set up an independent nation called Haiti.