– As Republican lawmakers promote an overhaul of the tax code, Senate Democrats are offering conditions of their own.

Forty-five members of the Senate Democratic caucus sent a letter to President Donald Trump and GOP Senate leaders Tuesday encouraging cooperation on tax reform but asking that Republicans not cut taxes for the wealthiest 1 percent of Americans. They also insisted that the reform effort not lower federal revenue.

Democrats also voiced opposition to Republicans passing a tax bill using reconciliation, a procedural maneuver that would allow the GOP to bypass Democratic support.

Fresh off their failure to pass a health care bill, Republicans have sought support for reconciliation to more quickly pass tax legislation in the fall. GOP Reps. Jason Lewis of Woodbury and Erik Paulsen of Eden Prairie have advocated the measure as they talk up tax reform to their constituents during the August recess.

“It’s been 31 years since major tax reform,” Paulsen tweeted Tuesday.

Paulsen and other GOP lawmakers say they’ll use all 31 days of August to highlight just as many reasons why tax reform is needed. They want to cut rates for corporations and individuals and simplify the tax code, though many of the details are still unknown.

U.S. Sens. Amy Klobuchar and Al Franken are among the Democrats who signed the letter, which also was addressed to Majority Leader Mitch McConnell and Senate Finance Committee Chairman Orrin Hatch. Only three senators in the 48-member caucus declined to lend their support.

“We are confident that, by working together, we could modernize our tax system to increase working families’ wages, improve middle-class job growth, promote domestic investment, modernize our outdated business and international tax systems and put in place sound fiscal policy that raises the revenue needed to meet the needs of our country,” Democrats wrote.

Republicans hope to have Trump sign a tax overhaul into law by December.