Henry W. Blair (1834–1920) was a U.S. Senator from New Hampshire from 1879 to 1891. Senator Blair may also refer to:

• Austin Blair (1818–1894), Michigan State Senate
• Craig Blair (born 1959), West Virginia State Senate
• Francis Preston Blair Jr. (1821–1875), Missouri State Senate
• John Blair (Tennessee politician) (1790–1863), Tennessee State Senate
• William Blair (American politician) (1820–1880), Wisconsin State Senate