Republican Sen. Jim Inhofe set off a scramble back in February when he would resign his seat at the end of this Congress. The 87-year-old’s well-timed announcement allowed for a special election for the remaining four years of his term.

There are 13 candidates competing in the Republican primary next Tuesday. While a large chunk of voters remain undecided — and thus the race could still go many ways — public and private polling has consistently shown 2nd District Rep. Markwayne Mullin atop the field with former state House Speaker T.W. Shannon in second place. If no candidate tops 50 percent — which is the likeliest outcome — an August 23 runoff would determine the GOP nominee.

Mullin, who was well-known in the Oklahoma City area as a prominent plumbing company owner before he was elected to Congress a decade ago has spent the most in the race, including $1 million of his own money.

Shannon also has high name ID in the state, having served as the first African-American speaker of the

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