Newt Gingrich - 34%
Mitt Romney - 31%
Rick Santorum - 16%
Ron Paul - 10%
Other - 2%
Undecided - 7%
Poll of 600 likely Republican primary voters, taken February 6-7, with a MoE of +/- 4%
A recent American Research Group survey finds Newt Gingrich and Mitt Romney leading the GOP field here in Oklahoma's presidential primary. The poll was conducted on February 6th and 7th, before Rick Santorum won the three states last night.
ARG is not well-know for being very accurate; in 2008, they were among the worst in accuracy rates among polling groups, so take the results with a grain of salt.
Romney, Paul and Santorum have fairly public campaigns in the state, whether grassroots or official campaign staff-led. Romney visited the state a few months ago, and Santorum is coming to Oklahoma City and Tulsa tomorrow. The major Super PAC supporting Gingrich has been running ads in the state for weeks (I've heard several different radio ads).