The Treaty was before the Senate, in secret session, from April 22nd until June 8th, when it was rejected by a vote of thirty-five to sixteen. It is not necessary to examine the reasons which moved the Northern Senators to vote against it, but it is important to understand some of the grounds upon which Senators from the slaveholding Commonwealths opposed it. Senator Benton declared that the Treaty annexed not only Texas but parts of four other Mexican provinces, which would be an international outrage upon Mexico. Most of the Southern Senators, however, were influenced by the fear of war with Mexico. But the most significant objection to it, from the point of view of subsequent events, was that urged by Mr. Archer, of Virginia, the chairman of the Senate committee for Foreign Affairs. He claimed that a foreign state could not be annexed to the United States by means of a treaty, and that, if a foreign state could become connected with the Union at all, it must be by means of an act of Congress. A large number of the Senators approved of this {309} doctrine. It was a pregnant idea to the President and Mr. Calhoun. It indicated that there was another way to accomplish annexation. While the Treaty was under consideration in the Senate, the national conventions for the nomination of presidential candidates had assembled. The Whigs had nominated Mr. Clay, who was regarded as opposed to annexation. The friends to annexation in the Democratic party had been able to put Mr. Van Buren aside, and had nominated James K. Polk, of Tennessee, an outspoken advocate of immediate annexation, and had made the "re-occupation of Oregon and the re-annexation of Texas" the chief plank in the party platform. [Sidenote: The new plan for annexation.] Here now were all the elements of a new plan for annexation, which promised more success. They were, the doctrine unwittingly advanced by Mr. Archer, and as unwittingly approved by many of the Senators, that Texas could be connected with the United States only by means of an act of Congress admitting her as a Commonwealth into the Union, the plank of the platform making annexation the chief issue of the campaign for the election of a new President and a new House of Representatives, and the connection of the Oregon question with that of annexation, in order to get votes in the North for both projects at once. On June 11th, President Tyler took the first step in the combination of these elements. He sent a copy of the rejected Treaty, and all the papers connected with it, to the House of Representatives, together with a message, in which he reviewed the subject and justified his position in regard to it, and declared, finally, that while he had regarded a treaty as the most suitable means for accomplishing annexation, he would {310} co-operate with Congress in the use of any other means compatible with the Constitution and likely to accomplish the result.