Hello! The short answer is yes!

Jefferson Davis (yep, that one) proposed an amendment to the Treaty Of Guadalupe-Hidalgo that the US should include annexation of the entirety of Coahuila, with parts of Tamaulipas, Nuevo Leon, and Chihuahua. However, there was a strong implication that it would introduce one (if not more) slave states, and a coalition of Whigs and Democrats defeated that amendment 44-11 and thus never made it to President Polk's desk. [3]

Also, I'm not sure if you intended to imply this - but Texas was not annexed in the Mexican-American War (It was annexed in 1845). The only part of Texas affected was that the Treaty of Guadalupe-Hidalgo established that Texas' border was at the Rio Grande River, and not the Nueces River (Mexico's claim)[1]. To quote directly from the treaty "...the two Republics shall commence in the Gulf of Mexico, three leagues from land, opposite the mouth of the Rio Grande..."[2]

Sources:

[1] James K. Polk's State of The Union Address - 1847

[2] Treaty of Guadalupe-Hidalgo Transcript

[3] The United States & Mexico 1821-1848 (Note: Page 634 is the text in question)