The Associated Press

SPRINGFIELD, Mo. — U.S. Rep. Kenny Hulshof fought back in a Wednesday night debate against what he derided as a “relentless, constant barrage of attack” by Republican gubernatorial rival Sarah Steelman, countering her portrayal of him as a big spender by casting her as an ally of Big Oil.

The televised debate, coming less than two weeks before the Aug. 5 primary election, provided some of the most testy exchanges so far in a campaign in which Steelman generally has been on the offensive.

Steelman, the state treasurer, has pounded on two themes in recent weeks — criticizing Hulshof for supporting wasteful spending earmarks in Congress and calling for a repeal of the state’s ethanol mandate.

Hulshof countered Wednesday by questioning some of Steelman’s own prior actions as a state senator, suggesting she backed anti-consumer utility legislation and effectively killed a nursing home abuse bill in 2000 by insisting on a provision that would have boosted nursing home payments by $133 million.

He asserted Steelman was buying into the spin of “multinational big oil companies” who are “trying to lay the energy woes of the nation on ethanol.”

Steelman replied: “I don’t buy into Big Oil. I buy into the free market system in this country that has always worked.”

She thanked Hulshof for raising the nursing home issue, saying her actions were “intended to make sure we were providing quality care to our nursing home residents in this state.”

The utility legislation, which allowed electric companies to more easily pass on the cost of fuel increases to consumers, was intended to let the state regulatory process work “in a way that would more accurately capture costs,” Steelman said.

The winner of the Republican primary is expected to face Democratic Attorney General Jay Nixon in the November gubernatorial election. Hulshof and Steelman are running because Republican Gov. Matt Blunt stunned supporters and foes alike by announcing in January that he will not seek re-election.

Hulshof and Steelman both have placed a campaign emphasis on southwest Missouri, traditionally the most Republican part of the state. In the 2004 gubernatorial election, for example, Springfield’s home of Greene County provided more than one-third of Blunt’s winning vote margin over Democrat Claire McCaskill.

On Wednesday, each Republican candidate claimed the conservative mantle, and each cited the other’s campaign contributions while questioning his or her resolve against embryonic stem cell research.