Ralph Hall forced into primary runoff
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Rep. Ralph HallRalph Moody HallGOP fights off primary challengers in deep-red Texas Most diverse Congress in history poised to take power Lawmakers pay tribute to Rep. Ralph Hall MORE (R-Texas), the oldest member of Congress, has been forced into a potentially perilous runoff in his primary against former U.S. Attorney John Ratcliffe (R).

The Associated Press called that the race will head to a May runoff, with Hall leading Ratcliffe by 45 percent to 30 percent with 27 percent of precincts reporting. 

A runoff could be treacherous for the 90-year-old congressman. Ratcliffe has already given his campaign close to a half-million dollars and is promising to donate more, while Hall, caught by surprise in the race, has very little money in the bank.

The low turnout in Texas's GOP primary runoff elections often favors more conservative candidates as well, which could benefit Ratcliffe, who has been running to Hall's right.

Ratcliffe's stated goal had been to make the runoff, while Hall's campaign had said they were hoping to win outright on Tuesday night.

Hall is the last World War II veteran to be running for reelection. This is the first time he's been forced into a runoff in decades despite switching from the Democratic Party a decade ago.