The Biographies:
John Quincy Adams -- often demonstrating his disdain for narrow partisanship, Adams (the son) was often at odds with his party (Federalist). He called for the embargo of 1807, somewhat ruinous to his own state's merchant interests.
Daniel Webster -- the outstanding orator of his day (from Mass), and a looker. Called the "living lie" because no man on earth could be as great as Webster looked. Bought into, and sold, the Clay Compromise that preserved the Union from 1850 until 1861, thus earning 50 years of infamy in his home district. Voted 5th most important senator ever by the senate in 1957.
Thomas Hart Benton -- "Old Bullion". With just one year at UNC, he was said to carry the entirety of the Library of Congress in his head. Opposed Calhoun's Texas treaty and other Calhoun disunion shenanegans, which his state (Missouri, a slave state) and party favored.
Sam Houston -- Governor of the state of Texas at the time of secession, he fought it tooth and nail. Alone. Brilliant far-seeing man. Which is why he would be alone in Texas.
Edmund G. Ross -- The guy who cast the deciding vote to acquit Johnson during his impeachment trial in 1868. The vote went mostly along party lines and he decided that it would be bad for the Union just to impeach a president on party lines (current Republicans have lost this compunction).
Lucius Quintus Cincinnatus Lamar -- sorry, too lazy
George Norris -- ditto
Robert A. Taft -- ditto
My favorite: Sam Houston. I gotta get a biography of him and read it sometime.