WASHINGTON (AP) — A Republican on the Senate Budget Committee said Tuesday that tax cut advocates on the panel are pressing for cuts that could add $1.5 trillion or more to the deficit over the coming decade.

Wisconsin Sen. Ron Johnson said he's backing "as aggressive pro-growth tax reform as we can get." He says a 10-year, $1.5 trillion tax cut "ought to be a minimum." He is among the many Republicans in Washington who promise that cutting corporate and individual rates and ridding the code of inefficient tax breaks, deductions, and preferences will boost the economy and cause a burst of new revenues.

Republicans on the panel are grappling over how much the ongoing tax cut push will add to the nation's $20 trillion-plus debt.

More deficit-conscious panel members, such as Sen. Bob Corker of Tennessee, are pushing back. Corker on Monday opposed an overwhelmingly popular defense measure that would smash the budget, saying "the inability to get our fiscal house in order is the greatest threat to our country."

The work of the budget panel is critical since Republicans need to agree on a Capitol Hill budget plan in order to pass a follow-up tax bill that's a centerpiece of the party's fall agenda without fear of a filibuster by Democrats. But both House and Senate Republicans are divided and the budget debate is months behind schedule.

"There's a spectrum of opinion inside our conference," Johnson told reporters who encountered him on a Senate sidewalk Tuesday morning. "We should be doing everything to grow our economy and part of that is as aggressive pro-growth tax reform as we can get."

Congress' impartial scorekeepers have accepted the premise of so-called dynamic scoring, but past studies by the Joint Tax Committee and Congressional Budget Office have been more pessimistic about how much economic growth and tax revenues would follow tax cuts.

"We cannot continue to do things the same way and deepen the fiscal crisis jeopardizing our national security," Corker said in a statement. He said he wants a budget deal this fall that would "responsibly funds our military without adding to our massive deficits."