(FORTUNE Magazine) – THE BUSINESS LOBBY'S ''No, never,'' on tax reform is turning into a ''Well, maybe.'' John M. Albertine, president of the American Business Conference, says, ''Overwhelming business support is not around the corner, but there's definitely a warming trend.'' Lobbyists now think the plan Treasury Secretary James A. Baker unveils this spring will be far more lenient toward business + than the one former Treasury Secretary Donald T. Regan proposed last Thanksgiving. Business had been particularly upset with two of Regan's proposals: killing the investment tax credit and scaling back depreciation allowances. Lobbyists have been feverishly working to preserve both provisions. The investment tax credit, which has been widely criticized as a costly and unnecessary subsidy to business, may be beyond saving. But many lobbyists believe Baker will loosen up on depreciation, a part of the current tax code that has been particularly helpful to capital-intensive basic industries. ''Treasury is stepping in the right direction,'' says Charls E. Walker, a tax lobbyist whose clients include Ford, Phelps Dodge, and Caterpillar. A less restrictive depreciation schedule is good news for the real estate business too. ''Baker's plan is likely to be less anti-investment and anti- home ownership than Regan's,'' says Jack W. Carlson, executive vice president of the National Association of Realtors. The housing industry doesn't expect to fare as well on two other Regan proposals it despises --tightening taxation of partnerships and allowing taxpayers to deduct unlimited interest only on primary dwellings. Baker hasn't indicated whether he'll rewrite Regan on those. Electronics companies disliked the Regan plan because it proposed taxing capital gains as ordinary income. ''As capital gains taxes go up, raising capital for risky high-tech companies goes to hell,'' says Kenneth Hagerty, vice president of the American Electronics Association. Baker's plan is expected to retain the tax break in some form. Several industries are still disenchanted with tax reform, at least until they hear more from Baker. Banks worry about a Regan proposal to raise their taxes by more than $12 billion in 1987, mostly by scrapping deductions for interest on debt used to finance holdings of tax-free bonds. ''We haven't seen anything that directly helps us,'' says Charles Wheeler, tax counsel for the American Bankers Association. Most business lobbyists think they'll get a better shake from Baker, not because he's more pro-business than Regan, but because he brings a fresh eye. Regan was intimately involved in the tax reform plan, lobbyists say, and it would have been tougher for him to accept changes.