WASHINGTON — Two weeks ago, Republicans passed their massive rewrite of the federal tax code. Now a Republican group is spending millions to convince voters they will benefit from it.

The American Action Network, a nonprofit group with close ties to Republican congressional leaders, is launching a $2 million round of TV ads promoting the tax bill Wednesday, the first salvo in a $10 million campaign to give key House Republicans a boost going into November’s midterm elections.

The ads, running in 23 districts, feature a couple sitting on their couch extolling the benefits of the bill – “will save a typical family more than $2,000”; “helps create jobs and boost middle-class income” – and thanking the local lawmakers for their votes.

So far, the public is not sold. Several public polls released last month, including surveys from CNN and the Wall Street Journal/NBC News show that pluralities of Americans oppose the tax bill, citing its benefits for corporations and the wealthy. Many Americans, the polls show, believe they will see a tax hike under the bill – not a tax cut.

The centerpiece of the $1.5 trillion bill is a dramatic cut in the corporate tax rate from 35 percent to 21 percent. Many business owners, meanwhile, will be entitled to a new 20 percent deduction on their business income, and wealthy Americans will see more of their assets sheltered from the federal estate tax. Wage earners see comparatively scant benefits – a larger standard deduction and child tax credit, as well as modestly lower income-tax rates, all of which will expire after 2025.

Democrats have been eagerly pointing to the outsize benefits for corporations and top earners, but Republican leaders believe that the public will warm to the bill once they see the benefits. For instance, employers are expected to start withholding less income tax from employee paychecks starting in February. “If we can’t sell this to the American people we ought to go into another line of work,” Senate Majority Leader Mitch McConnell, R-Ky., said after the Senate vote.