LITTLE ROCK — Increasingly bitter Republican campaigns for attorney general and the state Senate, which have featured critics of President Barack Obama being cast as his closest allies, come to an end Tuesday as voters cast their ballots in Arkansas' primary runoff election.

Light turnout was expected in Tuesday's election, with the only statewide matchup being the GOP contest for attorney general. The secretary of state's office has predicted that 3 or 4 percent of the state's 1.6 million registered voters will cast a ballot in Tuesday's election.

Little Rock lawyers Leslie Rutledge and David Sterling have spent the past three weeks jabbing at each other's conservative credentials and legal experience as they vie for the GOP nomination for attorney general. The winner of Tuesday's runoff will face Democratic state Rep. Nate Steel and Libertarian nominee Aaron Cash in the fall election.

Rutledge, 38, is a former lawyer for the Republican National Committee and ex-Gov. Mike Huckabee. Sterling, 45, is a former assistant city manager of Hope who has been in private practice for the past 15 years.

Rutledge finished first the May 20 primary but failed to win the majority needed to claim the GOP nomination outright. She's enjoyed a healthy fundraising lead over Sterling, but has been targeted by an outside group that's praised him for proposing a "Stand Your Ground" law. The ads and mailers by the Judicial Crisis Network have compared Rutledge to Obama and House Democratic Leader Nancy Pelosi for not advocating similar legislation.

Rutledge has denounced the ads, saying state law already allows the use of deadly force in self-defense. Sterling has said he didn't have anything to do with the spots, but said he doesn't believe they're inaccurate.

The two have also clashed over the death penalty. Sterling has proposed resuming executions and resorting to the electric chair while the state's lethal injection law remains in limbo because of court challenges. Rutledge has called the proposal irresponsible, noting that the state's electric chair is currently in a museum.

The Republican runoff for state Senate District 17 in northern Arkansas, which has focused primarily on the state's compromise Medicaid expansion, has similarly heated rhetoric. The race pits state Rep. John Burris, an architect of the "private option," against Scott Flippo, an assisted living facility owner who says he'll push for the program's end if elected.

Under the private option, Arkansas is using federal Medicaid money to purchase private insurance for the poor. More than 170,000 people have signed up for the program, which Burris and other supporters crafted as an alternative to expanding Medicaid under the federal health law.

Flippo and an outside group opposed to the program have accused Burris of embracing the federal health law they both deride as "Obamacare" by supporting the private option. Burris has said Flippo is misleading voters about the program. There's no Democrat running for the seat in the fall.

Tuesday's election also features a Democratic runoff for a southeast Arkansas House seat.