1Republican from Arizona, elected in 1986, 1992, 1998, 2004, and 2010
2Independent from Maine, elected in 2012
3Democrat from Minnesota, elected in 2006 and 2012
4Independent from Vermont, elected in 2006 and 2012
5Democrat from Ohio, elected in 2006 and 2012
6Democrat from Massachusetts, elected in 2012
7Democrat from Wisconsin, elected in 2012
8Republican from Alaska, elected in 2004 and 2010
9Democrat from Connecticut, elected in 2012
10Democrat from Vermont, elected in 1974, 1980, 1986, 1992, 1998, 2004, and 2010
11Republican from South Carolina, appointed
12Democrat from West Virginia, elected in 2010 and 2012
13Democrat from Illinois, elected in 1996, 2002, and 2008
14Democrat from Virginia, elected in 2008
15Democrat from Oregon, elected in 1996, 1998, 2004, and 2010
16Republican from Kentucky, elected in 2010
17Democrat from Rhode Island, elected in 2006 and 2012
18Republican from Utah, elected in 2010
19Republican from Maine, elected in 1996, 2002, and 2008
20Democrat from Colorado, elected in 2010
21Democrat from Delaware, elected in 2010
22Democrat from Pennsylvania, elected in 2006 and 2012
23Democrat from Oregon, elected in 2008
24Democrat from Montana, elected in 2006 and 2012
25Republican from Tennessee, elected in 2006 and 2012