US political analysts are calling the latest failure to repeal Obamacare in the Senate "the beginning of the unravelling" of Republican support for Donald Trump.

During a panel discussion on the President’s “skinny repeal bill”, which was voted down by a thin margin of 51-49 after three GOP rebellions led by Senator John McCain, CNN commentator Margaret Hoover warned that “Trump is clearly acting on his own; he’s not listening to anybody.”

Two other Republicans joined Senator McCain, Lisa Murkowski of Alaska and Susan Collins of Maine, on voting no on a bill that critics had warned would have led to the deaths of 20,000 additional people.

In a statement shortly after the results of the vote were announced, the senator for Arizona said: “From the beginning, I have believed that Obamacare should be repealed and replaced with a solution that increases competition, lowers costs, and improves care for the American people. The so-called ‘skinny repeal’ amendment the Senate voted on today would not accomplish those goals.

“While the amendment would have repealed some of Obamacare’s most burdensome regulations, it offered no replacement to actually reform our health care system and deliver affordable, quality health care to our citizens.”

Failure to pass the repeal act demonstrated a “haphazard policy-making process on behalf of the White House,” Ms Hoover added.

In response to the results, Democrat Senator Ed Markey of Massachusetts on CNN encouraged the US president to put aside partisanship and work together with Democrats: “We do want to work with Republicans. The Affordable Care Act has to be improved…but we have to do it on a bipartisan basis and hopefully those millions of Americans can sleep easier tonight knowing their healthcare has not been ripped away from them can now look to democrats and republicans finally coming together to make this healthcare system work better.”

The US president’s approval rating has plummeted in the last week following the GOP’s disunited front on the topic of Obamacare, as well as the US president’s criticisms following Attorney General Jeff Sessions' decision to recuse himself.

A Reuters poll conducted on the 24 July, less than a week before the vote on Obamacare found that just 35.1 per cent of GOP party members polled approved of the US president’s work. Over half (58.1 per cent) disapproved, and 4.1 per cent had “mixed feelings.”

Political scientist Matt Glassman echoed these sentiments, telling The New York Times: “The current congressional GOP seems less supportive and more constraining of the Potus than basically any in history.”