Clever speakers who were numerous in the Whig party at that day did not fail to see and seize their advantage.
The Mexican war had scarcely begun when the President justified the popular suspicion by making known to Congress that one of its objects was to be the acquisition of territory beyond the Rio Grande.

Perhaps it would be fairer to say that he expected such acquisition to be one of its results.

He ably vindicated the policy of marching a military force into the territory between the Nueces and the Rio Grande, by the fact that he was memorialized to do so by the still existing Congress of Texas, on the urgent plea that Mexico was preparing to move upon the territory with a view to its recapture.

In this Congress of Texas, the same body that completed the annexation, there were representatives from the territory in dispute beyond the Nueces; and the President felt that they were in an eminent degree entitled to the protection of our government.
Events were so hurried that in three months from the formal declaration of war, and before any victory of decisive significance had been achieved, the President sent a special message to Congress, in which he suggested that "the chief obstacle to be surmounted in securing peace would be the adjustment of a boundary that would prove satisfactory and convenient to both republics." He admitted that we ought to pay a fair equivalent for any concessions which might be made by Mexico, and asked that a sum of money should be placed in his hands to be paid to Mexico immediately upon the ratification of a treaty of peace.

As a precedent for this unusual request, the President cited the example of Mr.Jefferson in asking and receiving from Congress, in 1803, a special appropriation of money, to be expended at his discretion.