Total of 16 as of January 5, 2011

Democrats

Blumenthal, Richard -- CT

Coons, Christopher -- DE

Manchin, III, Joe -- WV

Republicans

Ayotte, Kelly -- NH

Blunt, Roy -- MO

Boozeman, John -- AR

Coats, Daniel -- IN

Hoeven, John -- ND

Johnson, Ronald -- WI

Kirk, Mark -- IL

Lee, Mike -- UT

Moran, Jerry -- KS

Paul, Rand -- KY

Portman, Rob -- OH

Rubio, Marco -- FL

Toomey, Patrick -- PA