How did the republican party grow so rapidly that within two years its candidates were challenging the established parties?

As the old parties broke up, antislavery zeal gave rise to the new Republican Party. Opposition to slavery was the center of the Republican philosophy. Attracting antislavery Democrats, Whigs, Free-Soilers and Know-Nothings, the Republican Party grew rapidly in the North.

(I got this answer straight from the history book, so you can copy it and you don't have to reWord it and it will be right)