Sen. Claire McCaskill (Getty Images photo via DayLife)

COLUMBIA, Mo. — U.S. Sen. Claire McCaskill, D., is once again pushing for a law that would increase taxes on the country’s top earners.

Touring the state during the Senate’s April recess, McCaskill renewed her call for the so-called “Buffett Rule,” a proposal, named after billionaire investor Warren Buffett, that would tax higher earners 30 percent on income above $1 million.

“That will help make the tax code more fair and level the playing field, and provide some needed revenue,” McCaskill said.

McCaskill denounced Republican charges that the tax increase would further stall the economy’s recovery and depress job creation.

“When the millionaires paid more in the 1990’s, we were creating jobs over jobs over jobs,” McCaskill said. “Compare job creation when taxes were slightly higher for millionaires, verses job creation after we gave them this tax cut in the Bush administration.”

“I’ve never seen the Republicans say there was a good time to raise taxes on multimillionaires,” McCaskill said, saying the issue boils down to the question of fairness in the tax code.

When McCaskill and her colleagues return to Washington later this month, they are expected to vote on the issue.

McCaskill is also highlighting her support for an end to tax breaks for the nation’s top oil companies.

McCaskill said in an effort to reduce gas prices, she supports more domestic oil production, ensuring oil companies aren’t “playing games” with refining capacity, and minimizing speculation by releasing oil from the nation’s strategic oil reserves.

“If we release some oil from the strategic reserve,” McCaskill said, “that would catch those speculators with their pants down, and that would be a good thing.”

McCaskill, who launched her tour Wednesday in St. Louis and Columbia, is expected to be in other regions of the state over the two weeks.