President Donald Trump made the pledge to repeal and replace Obamacare one of the key issues of his 2016 election campaign. But as Republicans try in earnest to make good on that promise, Trump appears to be losing influence.

Senate Majority Leader Mitch McConnell said Tuesday that GOP leadership would delay a vote on its healthcare bill, the Better Care Reconciliation Act, until after the weeklong July 4 recess because of a lack of support among Republican lawmakers.

Nine members of the party have publicly said they would not vote for the bill in its current form. McConnell can lose only two votes for the BCRA to pass, as all Democrats are expected to oppose it.

But Trump apparently isn't helping GOP members get to "yes." In contrast to his hard sell on the House healthcare bill, The Washington Post and The New York Times published reports late Tuesday saying Trump had done little to get the reluctant GOP senators to come to an agreement.

According to The Times' Glenn Thrush and Jonathan Martin, Trump has been "on the sidelines" during the Senate negotiations.

In fact, one Republican senator in favor of the BCRA told The Times that the president "did not have a grasp of some basic elements of the Senate plan" during a meeting with all of the GOP members on Tuesday. The senator also said Trump was confused when a moderate expressed concern that the bill would be seen as a tax break for the rich.

A Tax Policy Center analysis showed that the top 0.1% of earners in America would receive, on average, a $207,390 tax break from the BCRA.

The Times also reported that Republican senators, including McConnell, expressed frustration with ads from a pro-Trump nonprofit group attacking GOP Sen. Dean Heller for going against the BCRA. Heller is up for reelection in Nevada come 2018 and faces an uphill battle in a state Democrat Hillary Clinton won in last year's presidential election.

A senior Republican close to both the Senate and the White House also told The Post that Republican lawmakers thought Trump was a "paper tiger" and did not mind going "their own way."

The lack of deference, according to The Post, comes from a feeling among lawmakers that Trump lacks an understanding of policy and that his low approval numbers do not give him much political capital.

"Trump doesn't bring us any votes. He just doesn't," a source close to McConnell told Politico.

President Donald Trump in the Rose Garden of the White House on Monday. AP Photo/Evan Vucci

Sen. Susan Collins, a moderate GOP holdout on the Senate legislation, also criticized Trump's approach to the process while talking with reporters on Tuesday after the delay was announced.

"This president is the first president in our history who has had neither political nor military experience," Collins said. "Thus, it has been a challenge to him to learn how to interact with Congress and how to push his agenda forward. I also believe it would have been better had the president started with infrastructure, which has bipartisan support, rather than tackling a political divisive and technically complicated issue like healthcare."

Lawmakers were already wary of Trump's turnaround on the House bill. In just a few weeks, the president went from a White House Rose Garden ceremony celebrating the bill's passage to calling the bill "mean" during a private meeting with senators. Trump last weekend confirmed in a national TV interview that he called the bill "mean."

Trump's comments have become a rallying point for Democrats' attacks on the GOP healthcare effort and have already appeared in political ads.

Trump used Twitter on Wednesday morning to push back on the Times and Post reports.

"The failing @nytimes writes false story after false story about me. They don't even call to verify the facts of a story. A Fake News Joke!" Trump tweeted. "Some of the Fake News Media likes to say that I am not totally engaged in healthcare. Wrong, I know the subject well & want victory for U.S."

Trump also attacked The Post as "the guardian of Amazon not paying internet taxes" and "FAKE NEWS."

Amazon CEO Jeff Bezos owns The Post privately, and the two entities do not have a business connection. Tax experts have debunked Trump's suggestion that The Post helps Amazon avoid taxes.