From CNN's Xuan Thai

WASHINGTON (CNN) -- A Democratic campaign official flatly refuted Republican suggestions Thursday that Democratic Sen. Robert Menendez is considering withdrawing from the New Jersey Senate race in order to allow another candidate to take his place on the November ballot.

National Republican Senatorial Committee lawyers told reporters that they are prepared to fight such a move if Menendez were to step aside. Menendez is under investigation for his financial dealings with a non-profit organization.

"All of us believe, we know that Democrats are willing to go outside statutes, they're willing to go outside the case law and outside established precedent and legal procedure to accomplish political end," said Cleta Mitchell, the NRSC's outside counsel. "They've done it before and we're prepared not to let it happen again. We are standing guard to protect and enforce the law."

Mitchell is referring to the 11th hour decision by Sen. Robert Torricelli, D-New Jersey, to withdraw from the Senate race in 2002, allowing retired Sen. Frank Lautenberg, D-New Jersey, to take his place on the ballot.

But Phil Singer, spokesman for the Democratic Senatorial Campaign Committee, described the NRSC's claims as having "“no basis in reality."

"It is a transparent effort to change the subject," Singer said.

In the latest Rutgers-Eagleton Poll, Sen. Bob Menendez and Republican candidate Tom Kean are in a dead heat with 45% of likely voters favoring Menendez and 44% of likely voters favoring Kean.