U.S. Rep. Ralph Hall first ran for office in 1950 and first won his congressional seat when Jimmy Carter was president.
But the 91-year-old is facing the toughest test of his very long political career in Tuesday's Republican primary runoff.
As the oldest-ever member of the U.S. House, Hall is trying to stave off a challenge from the right by a candidate barely half his age, former U.S. Attorney John Ratcliffe.
His district stretches from suburban Dallas east to borders with Louisiana and Oklahoma.
Ratcliffe, 48, has used modern analytics to target voters and has support from national tea party groups. He says Hall's too cozy with the GOP establishment.
Hall has relied on a more-traditional campaign. But he bristles at suggestions he's not conservative enough for today's GOP voter.
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