The political campaign had now so far taken shape that its elements and chances could be calculated with more than usual accuracy.  The Charleston Convention had been disrupted on the 30th of April, and adjourned on May 3; the nomination of John Bell by the Constitutional Union party occurred on May 10.  The Chicago Convention met on May 16; and while there was at that date great uncertainty as to whom the dissevered fragments of the Democratic party would finally nominate, little doubt existed that both the Douglas and Buchanan wings would have candidates in the field.  With their opponents thus divided, the plain policy of the Republicans was to find a candidate on whom a thorough and hearty union of all the elements of the opposition could be secured.  The party was constituted of somewhat heterogeneous material; a lingering antagonism remained between former Whigs and Democrats, protectionists and free-traders, foreign-born citizens and Know-Nothings.  Only on a single point were all thus far agreed—­opposition to the extension of slavery.

But little calculation was needed to show that at the November polls four doubtful States would decide the Presidential contest.  Buchanan had been elected in 1856 by the vote of all the slave States (save Maryland), with the help of the free States of New Jersey, Pennsylvania, Indiana, Illinois, and California, Change the first four or even the first three of these free-States to the Republican side, and they, with the Fremont States of 1856, would elect the President against all the others combined.  The Congressional elections of 1858 demonstrated that such a change was possible.  But besides this, Pennsylvania and Indiana were, like Ohio, known as “October States,” because they held elections for State officers in that month; and they would at that early date give such an indication of sentiment as would forecast their November vote for President, and exert a powerful, perhaps a decisive, influence on the whole canvass.  What candidate could most easily carry New Jersey, Pennsylvania, Indiana, and Illinois, became therefore the vital question among the Chicago delegates, and especially among the delegates from the four pivotal States themselves.

William H. Seward, of New York, was naturally the leading candidate.  He had been longest in public life, and was highest in official rank.  He had been Governor of the greatest State of the Union, and had nearly completed a second term of service in the United States Senate.  Once a prominent Whig, his antecedents coincided with those of the bulk of the Republican party.  His experience ran through two great agitations of the slavery question.  He had taken important part in the Senate discussions which ended in the compromise measures of 1850, and in the new contest growing out of the Nebraska bill his voice had been heard in every debate.  He was not only firm in his anti-slavery convictions, but decided in his utterances.  Discussing the