Senate Democrats and their supporters had a unified message when it came to standing against Republican efforts to repeal and replace the 2010 health care law. But when it comes to resisting President Donald Trump and the GOP on tax legislation, it might get more complicated.

Democratic leadership is sending signals it is not willing to negotiate on the GOP tax bill until the current partisan effort fails, but some members of the conference appear ready to buck that message, if need be.

It’s a dramatic shift from the health care effort, when nearly every Democrat was immediately opposed to the GOP plan because they knew it would mean gutting former President Barack Obama’s signature domestic achievement.

And while lawmakers from both parties say health care is a far more electrifying issue for voters than taxes, some Democrats are holding out hope the public will be strongly opposed to the legislation when it is released.

“They’ve made this a messaging layup, and I think, ultimately, this bill, when it emerges, will be just as unpopular as their health care bill,” Sen. Christopher S. Murphy told said.

The Connecticut Democrat, who often takes a leading role on conference messaging, expects to have a rather straightforward case to oppose what the Republicans put forward.

“The tax bill is in some ways easier to message against than the health care bill — a big tax cut for the rich paid for by cuts to Medicare and Medicaid,” Murphy said. “I can say that in about six seconds and people understand all of it.”

GOP targets

But Sen. Cory Gardner, the chairman of the National Republican Senatorial Committee, has his doubts.

“It’s going to be very difficult for Democrats to unite against tax relief that grows wages, that brings jobs and businesses back to the United States and makes us competitive again,” the Colorado Republican said. “Quite frankly, if they are united on that message in opposition, it will mean significant problems for them in 2018 and beyond.”

“When all of a sudden tax reform passes, tax relief passes, and it’s with bipartisan support, I guess their message works in California, I guess their message works in New York, but it’s not going to work in Missouri, Indiana, North Dakota, Montana, you name it,” Gardner said.

That was of course not a random list of states rattled off by the leader of the Senate GOP campaign apparatus. Those four states have incumbent Democratic senators on the ballot next year who are being targeted by Republicans. And the GOP intends to make it difficult for those members to oppose the final bill.

While details are still under wraps, Republicans say they are considering a  proposal that could end up addressing concerns from the minority party. Instead of repealing the estate tax, for example, the GOP may instead double the tax exemption on money left to heirs. 

Breaks in the ranks

That may be why some lawmakers are not on board with Senate Minority Leader Charles E. Schumer’s assertion that Democrats won’t support any bill until the partisan effort fails.

“I’m ready to negotiate tax reform now. I will continue to engage with my Senate colleagues and the White House — that’s my job and Hoosiers expect me to do it. It doesn’t make sense to me to wish for it to fail before we even know exactly what it is,” Indiana Democrat Joe Donnelly said in a statement.

“The leader doesn’t speak for me. I have a voice of my own,” said Sen. Claire McCaskill, a Missouri Democrat. “I am anxious to see the first glimmer of some kind of effort to allow somebody to participate in this, besides Republicans.”

But while some provisions may garner the support of Democrats — particularly ones that members have supported in the past — Republican tax writers could also include items that would be easy for Democrats to oppose.

The recurring suggestion that Republicans may seek to reduce the cap on tax-deferred contributions to 401(k) retirement plans is opposed even by Democratic senators who might want to support a tax overhaul, like Heidi Heitkamp of North Dakota.

A former state tax commissioner, Heitkamp is among the targeted Democrats to which Gardner was referring.

“I’ve long said I’m eager to work with Republicans and Democrats on a tax reform package that simplifies the tax system and reduces taxes on hard-pressed middle income families and small businesses,” she said in a statement. “But I’m very concerned by reports that Republicans intend to reduce the tax-free contributions that working Americans put into their 401K plans to save for retirement. Taking that step would raise taxes on North Dakota families and reduce their retirement savings.”

Critics from a broad swath of groups generally supportive of Democrats are set to hold a rally outside the Capitol on Wednesday, when Ways and Means Chairman Kevin Brady was initially supposed to release the House GOP tax bill. Sources familiar with the matter said late Tuesday that the release had been delayed. 

At that event, organized by the liberal “Not One Penny” campaign, House Minority Leader Nancy Pelosi is scheduled to join Senate Finance ranking member Ron Wyden, Massachusetts Sen. Elizabeth Warren and several House Democrats.

Liberal groups including the Progressive Change Campaign Committee and MoveOn.org are organizing the pushback against the GOP-led tax plan under the Not One Penny banner, along with the Center for American Progress Action Fund and organized labor.

Other complications

Democratic messaging efforts may need to be somewhat different for the two sides of Capitol Hill if the eventual goal is to stop the Republicans in their tracks. That is because the House and Senate differ in terms of membership makeup.

The House Republican Conference includes no shortage of members from high-tax states, where efforts to curtail a deduction for state and local taxes are very unpopular. The majority of those states, however, have Democratic senators, all of whom have been shut out of the negotiations so far on the tax plan.

The messaging could also be made more difficult by the Democrats’ conflicting views on the plan. While some members — including Schumer — appear poised to oppose whatever plan Republicans release, others are keeping the door open.

“Chuck knows that I’ve got some problems with that,” Montana Sen. Jon Tester said of the blanket opposition. “We’re going to look at it and analyze it for what it is.”

Correction Nov. 1, 1:03 p.m. | An earlier version of this story should have stated that liberal groups, including the Progressive Change Campaign Committee, MoveOn.org, the Center for American Progress Action Fund and organized labor, are organizing the pushback against the GOP-led tax plan under the Not One Penny banner.