Republicans and Democrats clashed in the Senate on Monday over President Obama’s proposal to boost taxes on the rich, an issue that similarly divided two Virginians who aspire to be in the chamber — George Allen (R) and Timothy M. Kaine (D).

The two former governors and candidates to succeed retiring Sen. James Webb (D) fall on opposite sides of the “Buffett Rule” — a plan named after billionaire investor Warren Buffett that would immediately make people earning $2 million or more pay a minimum income tax rate of 30 percent, while gradually forcing those earning at least $1 million to do the same.

Obama and his fellow Democrats see the rule as an important step toward a fairer economic system, but Republicans dismiss it as a divisive stunt. Allen, for his part, would vote against the proposal if he were in the Senate, according to campaign spokeswoman Katie Wright.

“This bill does nothing to help create jobs or lower the escalating prices of fuel and food,” Wright said. “Virginians are looking for comprehensive tax reform that will make the complicated federal tax code simpler, fairer and more competitive — not more political gimmicks from Washington.”

Kaine’s camp jumped on Allen’s opposition to the measure.

“If George Allen were serious about comprehensive tax reform,” said Kaine spokeswoman Lily Adams, “then he wouldn’t be running for reelection on a record of defending tax breaks for big oil companies and calling for more tax cuts for the wealthiest Americans while promising to balance our budget through cuts to defense, education, Medicare and other programs central to Virginia’s and the nation’s economy.”

Monday’s sparring followed a similar debate last week, after Kaine questioned the value of focusing on the Buffett Rule.

In an interview Thursday with Charlottesville radio station WIMA, Kaine suggested that the proposal amounted to “tripping over dollar bills to pick up pennies.”

Kaine said “the content of it is fine, but I do question a little bit the priority of doing this right now,” because the proposal would have relatively little impact on the federal deficit. Instead, Kaine reiterated a point he had made before: that letting the Bush-era tax cuts on those making over $500,000 expire would go a much longer way toward balancing the government’s books.

National Republican Senatorial Committee spokesman Brian Walsh said “it speaks volumes when Tim Kaine is criticizing President Obama, of all people, for not taxing and spending nearly enough. This is just more evidence that Tim Kaine is a tax-and-spend liberal who is more focused on growing government, rather than growing jobs in Virginia.”