Donald Lambro

The winner of the Republican presidential nomination will probably be the candidate who most embodies the core principles and beliefs of Ronald Reagan.

But the front-runners for their party's nod -- Arizona Sen. John McCain and former New York mayor Rudolph Giuliani -- have sent mixed signals on the centerpiece of Reagan's domestic agenda: tax-rate cuts to achieve maximum economic growth.

While both have said President Bush's across-the-board income tax cuts should be made permanent before they expire in 2010, neither have signed the pledge that every Republican presidential nominee has signed since 1988 promising not to raise the tax rates.

And as of last week, neither of the two candidates were willing to say they soon would sign it, raising concerns among the GOP's economic conservatives that they were going a little wobbly on the party's promise to reduce taxes to the lowest possible level.

The issue was especially troubling for McCain because he was one of only two Republican senators who voted against the Bush tax cuts in 2001 and who voted against accelerating them in 2003. He abruptly flip-flopped last year, voting to extend some of the tax cuts, when he began actively running for president.

Until that time, he was a foe of his party's tax cuts, telling his colleagues in the Senate, "I cannot in good conscience support a tax cut in which so many of the benefits go to the most fortunate among us at the expense of middle-class Americans who need tax relief."

That's a statement no Democratic presidential contender today would disagree with, but it was sheer apostasy to his party's conservative base.

"I can't imagine that McCain wouldn't sign it or that Giuliani wouldn't sign it. I can't imagine any Republican not signing that," said Jack Kemp, the architect of the income tax cuts that became the hallmark of Reagan's presidency.

The pledge is a short, written statement, circulated by Americans for Tax Reform to all the candidates, that simply states they will "oppose any and all efforts to increase the marginal income tax rates."

Tax-cut crusader Grover Norquist, ATR's president, has turned the pledge, started in 1986, into an election ritual that no serious Republican candidate for president has refused to sign: Former president Bush signed it in 1988, as did Bob Dole in 1996 and George W. Bush in 2000.

Thus far, Massachusetts Gov. Mitt Romney (on Dec. 31), Kansas Sen. Sam Brownback, California Rep. Duncan Hunter and former Virginia governor James Gilmore have all signed the pledge. Nebraska Sen. Chuck Hagel (though he has previously signed it as a senator) and former Arkansas Gov. Mike Huckabee have not.

Donald Lambro

Donald Lambro is chief political correspondent for The Washington Times.