Ivanka Trump thrust her paid family-leave plan back into the spotlight this week, writing a defense of the White House’s proposal for the Wall Street Journal. The program, she wrote, would not be an entitlement, as her critics have charged, but “an investment in America's working families.”  

The missive came after an editorial in the newspaper slammed her proposal in May, arguing it would open the door for future Democrat administrations to beef up the benefit at great expense.

But the president’s eldest daughter, who is also one of his official West Wing advisers, faces a bigger political hurdle than unfavorable opinion columns. Liberal lawmakers won’t back the plan, arguing it doesn’t go far enough to support low-income parents. And Republicans aren’t getting on board, either — not even the GOP leaders who support the idea of paid leave.

Take Sen. Marco Rubio (R-Fla.), who met with Trump last month to discuss child-care policy. Rubio has praised the first daughter for tackling an issue Republicans have only recently begun to address — the party’s traditional stance is that a healthy economy would support families better than a broad government mandate — but he has not endorsed Trump’s particular proposal.

“Ivanka Trump has been a leader on making pro-family issues an essential piece of tax reform,” his office said in a June statement. “The meeting between Ivanka Trump and members of Congress demonstrates the momentum for this push.”

Applauding momentum for Trump’s pro-family efforts, however, isn't the same as explicitly supporting her plan.

“Ivanka faces a major dilemma in having to construct a plan that appeals to both Republican lawmakers and the longtime advocates of paid leave on the left,” said Samuel Hammond, a policy analyst at the libertarian Niskanen Center. “Too generous, and the plan will be dead in the water. Too weak, and the left will excoriate her. It's not an enviable position to be in.”

Currently, the United States doesn’t guarantee a single day of paid time off for new parents.

The White House plan that Trump is promoting would provide six weeks of paid family leave to new mothers and fathers whose employers do not supply the benefit, to be paid through the nation’s unemployment insurance system.

The estimated cost would reach $25 billion over 10 years, and the president’s proposed budget cuts from other national programs would cover it, according to the Office of Management and Budget.

“We wanted to take the initiative to present a strong proposal in our budget as a stake in the ground,” a White House official said. “This is a high-priority issue and the administration is exploring all options, meeting weekly with Congress and leaders from outside the government on the ultimate paid leave proposal that will work for all working families. We know how hard it is going to be and that for all the talk on the issue, nobody has been able to get it done before, but we are committed to it.”

Rubio’s approach to paid leave is starkly different from Trump's proposal. Two years ago, he pitched a new Child Tax Credit worth $2,500 per child, becoming the first GOP presidential candidate to release a proposal on the issue. He has also backed tax cuts for companies that provide paid leave to their employees. (Rubio’s office would not comment on Trump’s plan.)

Then there’s Sen. Deb Fischer (R-Neb.), who has advocated for more support of working parents for years. Trump met with her last month, too.

Fischer, however, has other thoughts on how the country should handle paid leave.

Earlier this year, she introduced a bill that would create a tax break for businesses that cover paid leave for employees after the birth of a child. As for Trump’s plan — well, she doesn’t seem to be wild about it.

“Senator Fischer appreciates Ivanka’s work on the issue and is continuing to push her proposal (the Strong Families Act) that she introduced three years ago,” her press secretary Brianna Puccini said in an email.

Another conservative lawmaker Trump has reportedly met with is Rep. John Katko (R-N.Y.), who last year proposed allowing workers to prepare for maternity or paternity leave with a tax-free savings account.

Asked if Katko endorses Trump’s vision on paid family leave, his deputy chief of staff Erin O’Connor replied in an email, “Rep. Katko has introduced his own measure” and provided a link to the details.

Senate Majority Leader Mitch McConnell (R-Ky.), meanwhile, sponsored a measure last year that would have allowed companies and workers in the private sector to convert overtime wages into paid family leave.

He has not offered thoughts on Trump’s proposal. “I'll be sure to let you know if the Leader makes a statement on this,” a representative for McConnell wrote in an email.

Staffers for Sen. Johnny Isakson (R-Ga.), who sponsored the overtime bill with McConnell, were more blunt, asserting that the lawmaker has not thrown his support behind the first daughter’s plan. "We haven’t had enough time to assess how the proposal would impact states and the private sector," spokesperson Amanda Maddox said.

Trump’s proposal might never become a bill, but she has already won a tough battle: sparking a robust, bipartisan debate regarding paid leave, said Aparna Mathur, an economist at the American Enterprise Institute, a right-leaning think tank.

“I think the idea is not to propose a plan but to get both sides first to say that a policy is needed,” said Mathur, who discussed paid leave with Trump at the White House last month, “then work with both sides to decide on the actual plan.”

The fact that lawmakers can’t seem to agree on one approach “makes a lot of sense,” she said. “I think they are wary of offering a concrete plan and then facing pushback on the details, rather than having people support the policy in general.”