Republicans thought the historic overhaul that slashed taxes would be one of their main campaign selling points ahead of November elections. Instead, Democrats are talking more about the law — and how they want to undo it.

In their bid to retake control of Congress, many Democratic candidates are pointing to the $1.5 trillion tax cut — and what they say are its exclusive benefits for corporations and wealthy individuals — as a roadblock to expanding benefits like Social Security and Medicare. Chipping away at some of the law’s costly provisions will help to fund those programs, they say.

(Related: IRS Nixes Anticipated Pass-Through Tax Deduction Workarounds)

“Democrats are able to go on the offense rather than be on defense,” said Celinda Lake, a Democratic pollster.

While Democrats are campaigning against the tax cut, Republicans have been quietly shelving it and focusing more on cultural and social issues such as immigration. Polls consistently show less than half of Americans approve of the tax cut.

There isn’t a formal list of agreed-upon tax policy changes, but some specific targets are emerging from discussions taking place within Democratic circles, including raising the corporate rate above 21 percent and changing the treatment of capital gains and carried interest. Other proposals, like repealing the new cap for state and local tax deductions and modifying the tax break for business owners, are proving to be more divisive.

So far, Democratic leaders have urged candidates to campaign on the issues they think will resonate in their districts, which has led to a wide array of messages. Representative Richard Neal of Massachusetts, the top Democrat on the tax-writing House Ways and Means Committee, has been hesitant to put out an economic plan while in the minority. And the House’s agenda will also be shaped by whomever serves as speaker, if Democrats regain control.

Polling, fundraising and voter turnout in primaries indicate Democrats have a good shot of taking control of the House but have a much tougher road gaining a Senate majority. If Congress is split, any tax legislation House Democrats pass would likely die in the Senate or face a veto from President Donald Trump. But a House Democratic tax plan could serve as a blueprint for the changes the party would push for if it regains the Senate or wins back the White House in 2020.

(Related: Clock Is Ticking on SLAT Estate Tax Exemption)

Here are some of the tax provisions on the Democrats’ radar:

Increase Corporate Tax Rate

Democrats are finding success — particularly among blue collar workers over 50 — by tying the corporate tax cuts to future reductions in Medicare, Medicaid and Social Security, Lake said.

Slashing the corporate tax rate to 21 percent from 35 percent is estimated to cost $1.3 trillion over the next decade, according to estimates from the nonpartisan Joint Committee on Taxation. Increasing the rate, by at least a few percentage points, is likely to figure in Democrats’ sights as a way to offset the costs of other investments.

In an infrastructure plan released in March, Senate Democrats called for a 25 percent corporate rate. More moderate House Democrats, including Neal, have said they’re supportive of a rate in the mid-to-high 20s. Representative John Delaney, a Maryland Democrat who is running for president in 2020, has called for increasing the corporate rate to 23 percent and to use additional revenue to fund infrastructure.

Hike Capital Gains Rates

The tax law didn’t change the treatment of capital gains, but the Treasury Department is looking at whether it has the power to cut tax bills for investors who have investment income. Democrats are already blasting the proposal, and a group of Senate Democrats wrote a letter to Treasury Secretary Steven Mnuchin, urging him not to index the gains to inflation.

Senator Ron Wyden of Oregon, the top Democrat on the Senate Finance Committee, has called for increasing the capital gains tax levy above the current 20 percent rate. Senators Bernie Sanders, a Vermont independent, and New York Democrat Kirsten Gillibrand, have pushed for a 0.5 percent tax on stock trades and 0.1 percent tax on bond trades, which could greatly increase the cost of high-frequency and high-volume transactions.

Both represent plans to target wealthy individuals and raise revenue that could help finance a major change, such as a Medicare-for-All program, advocated by Alexandria Ocasio-Cortez running in New York, or tuition-free college. But a substantial increase in those rates could be a dealbreaker for many donors, as well as more business-friendly Democrats.

The math is complicated if Democrats want to fully fund the government, plug the revenue lost by the tax law and create new programs, said Frank Clemente, executive director at Americans for Tax Fairness.

“If you add all those things up, it will be trillions of dollars,” Clemente said. “I’m not sure anything lends itself to a bumper sticker.”

Repeal Carried Interest Break

Eliminating special tax treatment for the profits hedge fund and private equity managers earn, known as carried interest, is also at the top many Democrats’ tax to-do lists.

Trump had previously vowed to end the provision that allows fund managers to pay capital gains rates, instead of higher ordinary tax rates, on much of their earnings. Instead, the tax law just extends the period — to three years from one year — that managers have to hold the assets for before they can qualify for the break.

Carried interest is politically easier to take on by Democrats and harder for Republicans to defend, according to Jason Fichtner, an associate director at John Hopkins University’s master of international economics and finance program.

Even though it would score political points, rolling back the provision would only raise about $19.9 billion over a decade, according to the Congressional Budget Office, a relatively small amount that would fund a small fraction of Democrats’ possible economic policies.

Revise Small Business Taxes

Modifying the law’s generous tax break for so-called pass-through entities, whose owners report their businesses’ income on their personal tax returns, is a sticky one for Democrats.

Some, such as Sean Casten, the Democrat facing Republican Representative Peter Roskam in a suburban Chicago district, have called to repeal the 20 percent deduction completely because of its complexity.

Others, like Katie Porter, the Democratic nominee running against vulnerable Representative Mimi Walters in Orange County, California, are calling for legislation that would lower taxes even further for small businesses.

The pass-through deduction was one of the most hotly debated and rewritten provisions as the tax law moved through Congress last year. Lawmakers struggled to find a balance between cutting taxes for pass-throughs without effectively creating a new way to shelter income from the Internal Revenue Service. Repealing the deduction without another plan to reduce taxes for small business would likely be hard to accept for many Democrats.

Undo SALT Limit

The tax law capped the amount of state and local taxes an individual can write off at $10,000. The amount was previously unlimited, and the cap hit residents of high-tax states in New York, New Jersey and California particularly hard.

Repealing or increasing the cap on that deduction is a high priority for Democrats who represent districts in high-tax states, such as Representative Bill Pascrell of New Jersey and John Larson of Connecticut.

But outside the high-tax states, there isn’t much political pressure to change the deduction, which could cost about $100 billion a year to restore in full, according to estimates from the Joint Committee on Taxation.

There’s also the argument that undoing the limit would ultimately benefit top earners in high-tax states the most.

“It could pick up some political points but it’s a revenue loser,” Fichtner said. “From a conservative standpoint, I would start to smile if the socialists were fighting with the progressives who were fighting with the moderate Democrats.”

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