Senate Democrats’ top political and policy-making strategist is imploring members of his party to abandon a tax reform principle members of both parties increasingly share: that Congress should reform the tax code by closing myriad, costly loopholes, and then use the new revenue to lower tax rates across the board, particularly for the wealthiest.

It’s a break with an increasingly bipartisan orthodoxy, first forged in 1986 when it served as the basis of Ronald Reagan’s tax reform, and more recently with a tax reform model promoted by the chairmen of President Obama’s commission on fiscal responsibility, Alan Simpson and Erskine Bowles.

It’s also an admission that the approach requires adopting a losing negotiating posture.

“Tax reform 25 years ago was revenue-neutral. It did not strive to cut the debt. Today, we can’t afford for it not to,” Schumer will say at the National Press Club Tuesday. “It would be a huge mistake to take the dollars we gain from closing loopholes and put them into reducing rates for the highest income brackets, rather than into reducing the deficit.”