Which of these political parties was started as a third party for supporters of the abolitionist movement

-Whigs

-Democrats

-Federalists

-Republicans

I'm pretty sure it's Whigs

The Whigs party.

Explanation:

Historians' studies revealed Whig party supported prison reform, educational reform, abolition of capital punishment; and temperance. Although the Whig party was not really an antislavery party, free blacks and abolitionists greatly preferred it more than proslavery Jacksonian Democrats.