A new survey from plumbing-company owner Markwayne Mullin’s campaign shows him leading the GOP field for retiring Rep. Dan Boren’s (D) competitive southeastern Oklahoma seat.

Mullin had 30 percent in the poll, state Rep. George Faught had 15 percent and former state Rep. Wayne Pettigrew had 7 percent. Thirty-four percent of voters were undecided in the survey, which was paid for by Mullin’s campaign.

There’s a good chance the winner of the June 26 Republican primary could come to Congress. Oklahoma’s 2nd district leans Republican, and Sen. John McCain (R-Ariz.) won it with 66 percent in 2008 even though Boren has always won re-election by substantial margins.

Democrats are confident their recruit, former Assistant U.S. Attorney Brad Wallace, has a strong shot in the general election. Wallace faces seed company owner Wayne Herriman in the primary, but local Democratic officials have coalesced behind Wallace.

Attorney Julie Carson, the wife of former Rep. Brad Carson (D-Okla.), backed Wallace today. The endorsement was widely viewed as a proxy for the former Congressman, who cannot interfere with partisan politics in his current role as general counsel for the army. Former Oklahoma Gov. Brad Henry (D) has also backed Wallace.

The Cole Hargrave Snodgrass & Associates poll took the opinion of 400 likely GOP voters in the 2nd district on June 4-5. The poll’s margin of error is 4.9 points. Here’s the full polling memo:

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