WASHINGTON - Donald Trump is in danger of losing his grip on the Republican Party as fears grow that he is headed for a defeat to his Democratic rival Hillary Clinton in November that will wipe out the party's majority status in Congress, according to political observers.

The cascade of Republicans seeking separation from Trump reached new levels this week and was punctuated by several high-profile defections, including centrist Republican senator Susan Collins of Maine.

Scores of current and former Republican lawmakers and officials have similarly declared their intention to either sit this election out or cross party lines in the fall.

Three weeks from the Republican convention in Colorado, polls show that Trump failed to increase support from within his own party, even as Democrats and former supporters of Bernie Sanders have steadily moved behind Mrs Clinton.

There is a growing chorus of conservatives calling on the Republican National Committee to cut Trump loose and direct its resources to protecting the party's majorities in the House and Senate.

Republicans see the presidential race approaching a crossroads. They say Trump has about a three-week window to turn things around or face full-scale abandonment by the national party.

That would be a disaster for Trump, who is running a barebones campaign that relies heavily on the RNC for battleground staff and other basic functions.

“He’s in big trouble right now,” Republican strategist Ron Bonjean was quoted as saying in The Hill, a newspaper dedicated to covering Comgress. “If we’re at this same point after Labour Day where it looks like we’re still spiraling into a black hole, I fully expect you’ll start to see resources directed to protecting our majorities in the House and Senate.”

The Trump campaign and Republican National Committee, the party's executive body, insist that tensions between the two are being blown wildly out of proportion by the media and that there is no chance the two are headed for a split.

The RNC has repeatedly denied rumours of interventions aimed at making Trump a more disciplined candidate. This week, the RNC disputed a bombshell report that chairman Reince Priebus had warned the candidate that the national party would leave him behind if he didn’t get his act together.

Trump campaign officials are similarly exasperated by the reports.

Adviser Kellyanne Conway called talk about the RNC abandoning Trump “wishful thinking” by his opponents, and said that contrary to media reports, the RNC and the campaign are working in concert to map out a victory strategy.

Priebus introduced Trump at a rally in Pennsylvania on Friday in a show of solidarity. But over the past few weeks, Trump has kept questions about tension between the two alive by repeatedly taking shots at Priebus and his allies.

Trump infuriated Priebus earlier this month by initially refusing to back his friend Paul Ryan, the Speaker of the House and highest-ranking Republican in the nation, in his re-election bid against a little-known outsider.

And Trump this week mused about how the RNC would suffer if it cut ties with him because he’d stop raising money for the national party.

Republicans interviewed by The Hill say they don’t expect Priebus or RNC officials will ever publicly come out against Trump. But they say the race could soon get to point where donors begin starving Trump of funds by earmarking money for Congressional races.

The RNC, they say, could quietly make the kinds of adjustments that would benefit down-ticket candidates to the detriment of Trump.

The message would shift from electing Trump as president, to encouraging voters to elect a Republican Congress to hold Clinton accountable in the White House.

“Every week that Trump doesn’t close the gap in a significant way, we are moving closer to that,” one former adviser to John McCain’s 2008 presidential bid who requested anonymity was quoted as saying.

“You don’t necessarily need a press conference to do it,” the ex-adviser said. “If field staff starts getting moved around, advertising resources get moved around, you can read the tea leaves and see where the action is and the focus of the party is.”

But Trump’s first concern, Republicans say, is keeping the trickle of Republican officials who have already abandoned him from turning into a flood.

Collins this week became the latest high-profile Republican to say she won’t be voting for Trump.

Others, like Congressmen Richard Hanna and Reid Ribble, are considering supporting the Libertarian Party ticket, which consists of two former Republican governors, Gary Johnson of New Mexico and Bill Weld of Massachusetts.

A new round of polls released by NBC on Friday found Trump mired between 29 and 36 percent support in four battleground states amid growing support for Johnson.

Meanwhile, the Clinton campaign is openly courting Republicans, launching an initiative focused on recruitment and outreach to conservatives and right-leaning independents.

The Clinton campaign is touting endorsements from nearly 50 Republicans, including current and former members of the House and Senate, former cabinet secretaries, ambassadors, business people, billionaire conservative activists and leaders in the armed forces.

And among likely Republican voters, Trump’s support has remained stagnant. A Monmouth University survey released this week found 92 percent of Democrats saying they’ll support Clinton, up from 88 percent in July and 85 percent in June. Trump’s support among Republicans has been stuck at 79 percent support since June.

“None of this is good news, but it can all be erased and forgotten with a great debate performance,” Republican pollster Frank Luntz said. “No one is really paying attention to the election right now — August is always the slowest month of the political year.”

“But come September, Trump will need a more unified, strategic and disciplined message and party,” he added. “Labour Day is the pivot point. And a brilliant debate performance changes everything.”

The first presidential debate is on September 26 in New York.

Trump’s supporters are fed up with talk about a GOP revolt against the candidate. They accuse the media of obsessing over a small group of disgruntled members of the Republican consultant class that they say are out of touch with where the rest of the party is.

Morton Blackwell, an RNC member from Virginia and Trump supporter, said he’s fielded several phone calls from fellow RNC members seeking an emergency meeting to recall Trump as the nominee.

Those efforts come as more than 70 anti-Trump Republicans signed a letter to Priebus urging him to abandon Trump and focus on protecting the party’s Congressional majorities.

“It’s patently absurd, it’s a lot of nonsense,” Blackwell was quoted as saying in The Hill. “A lot of ink will be spilled and electrons will be radiated on these matters because they’re titillating, but it is completely unrealistic. The RNC has a responsibility to help its candidates at every level.”

Blackwell said the defections don’t represent a full-scale movement away from Trump. He believes that with about three months to go, there is plenty of time for the candidate to turn things around.

“This is the most unpredictable national election we’ve had in my lifetime and a lot of people who make their livings reading crystal balls are going to end up eating ground glass,” Blackwell said. “It is unpredictable and I expect it will remain unpredictable.”