Which of the following statements is true of the free-soil party? check all of the boxes that apply. 1) both whigs and democrats joined the party. 2) the party opposed the extension of slavery into the territories. 3) southerners outnumbered northerners in the party. 4) the party promoted abolitionism as its primary issue. 5) martin van buren ran as the party’s nominee for president. 6) the party had no impact on the election of 1848.