OKLAHOMA CITY - An exclusive News 9/News On 6 poll shows Republicans Jim Inhofe and James Lankford hold big leads in their races for U.S. Senate seats.

When asked who they would vote for if the election were held today and they were standing in the voting booth, more than half of the voters polled said they would pick both Inhofe and Lankford.

Inhofe, who is seeking re-election on November 4, 2014, would get 59.1 percent of the vote. His closest challenger is Democrat Matt Silverstein, an investment planner from Bixby, with 27.4 percent.

Independent Ray Woods would get 1.7 percent, as would Independent Aaron Delozier. Independent Joan Farr would get 1.2 percent of the vote.

In the race to replace retiring Senator Tom Coburn, M.D., fellow Republican James Lankford would get 58.2 percent of the vote. Lankford has represented Oklahoma's 5th District in the U.S. House since 2011.

His closest challenger is Democrat Constance Johnson, who's represented the 48th District in the Oklahoma State Senate since 2005. According to our poll, she would get 28.1 percent of the vote.

Independent Mark Beard would get 3 percent of the vote.

In that race, 10.7 percent said they're unsure for whom they'd vote.

About the poll: SoonerPoll conducted the surveys by telephone on August 28-30, 2014 of 603 likely voters registered to vote statewide in Oklahoma. The margin of error is + or – 3.99 percent. The results were weighted by age and sex, stratified to Oklahoma likely voter demographics.