(CN) - Republican presidential candidate Donald Trump declared the "shackles" are off on Tuesday and immediately lit into House Speaker Paul Ryan and other GOP lawmakers that have rebuked him in recent days over vulgar comments he made a decade ago.
With just four weeks to go before Election Day and his campaign reeling, Trump returned to the combative form he displayed on the campaign trail during the Republican primaries, blasting critics in his own party.
Trump is particularly angry with House Speaker Paul Ryan, who during a conference call with House GOP lawmakers on Monday said he will, "no longer defend Donald Trump" and will instead devote his energies over the next four weeks to "making sure that Hillary Clinton does not get a blank check" with a Democratic Congress if she's elected president.
"Disloyal R's are far more difficult than Crooked Hillary," Trump said in one of a string of Tweets he posted Tuesday. "They come at you from all sides. They don't know how to win - I will teach them!"
Minutes later, he was firing again, saying, "With the exception of cheating Bernie out of the nom the Dems have always proven to be far more loyal to each other than the Republicans!"
He went on to dismiss Paul Ryan as a "weak and ineffective leader" and slammed "the very foul mouthed Sen. John McCain" who Trump says "begged for my support during his primary (I gave, he won), then dropped me over locker room remarks!"
He summed up his feelings this way: "It is so nice that the shackles have been taken off me and I can now fight for America the way I want to."
The unrestrained series of Tweets sent off shock waves in GOP circles, where many fear an all-out civil war has broken out precious few days before the Nov. 8 election, and worse, that Hillary Clinton's jump to a double-digit lead in the latest polls may signal the end of Republican control of the Senate and heavier than expected losses in House races across the country.
On WOR-FM in New York, Todd Schnitt, an avowed Trump supporter who co-hosts a morning show with Len Berman, the esteemed former sportscaster and a Democrat, actual mused about the possibility of the GOP losing the House and ushering in a new era of "House Speaker Nancy Pelosi."
In fact in a presidential election year like no other, the latest turn of events in unprecedented in the history of presidential politics.
And Republicans, speaking privately, say they now fear Trump is careening toward an epic loss in the wake of the release of the 10-year-old tape in which he makes inflammatory comments about women.
Those remarks triggered a mass defection by Republican lawmakers, and published reports Wednesday suggest that at least a quarter of GOP elected officials across the country are now withholding their support from the party's standard-bearer.
In red states like South Carolina, where Trump is almost guaranteed to win next month, tepid support remains.
Most political observers say it's a practical matter.
While it's safe to condemn Trump's remarks in the Palmetto State, no elected official wants to cut off his nose to spite his face and inspire the ire of South Carolina's Republican voters.
U.S. Sen. Tim Scott has said he will continue to back Trump for president because "he's the lesser of two evils."
North Charleston Mayor Keith Summey, who endorsed Trump prior to the South Carolina primary, has said he simply will not talk about the billionaire real estate developer anymore.
A statement released by the city on Monday said "Going forward, Mayor Summey will not be sharing his opinions on the presidential election."
It continued: "People should vote their own convictions, and not rely on someone else to make that decision for them."
However, the state's senior U.S. senator, Lindsey Graham, has been more adamant in expressing his views.
"I can't go where he's taking the party or the country," Graham said.
The crowd of Republicans joining that chorus grew a bit larger on Wednesday as 13 transportation, energy and environmental officials from George W. Bush's administration released a statement opposing Trump's presidential bid.
None of the officials has ever publicly opposed a GOP presidential nominee. They say they are compelled to now because Trump doesn't stand for the Republican Party's principles.
Fifty former Republican national security officials signed a similar statement last summer.
Meanwhile, Alaska's two U.S. senators have resigned leadership posts in the state Republican party after denouncing rump and calling for him to step aside.
Party officers are expected to back party candidates.
Sens. Lisa Murkowski and Dan Sullivan voluntarily resigned over the weekend as honorary members of the party's state central committee.
In the face of all this, and after some called for him to replace Trump at the head of the GOP's ticket, Indiana Gov. Mike Pence sought to staunch the bleeding Wednesday, telling students at Liberty University in Lynchburg, Virginia that this is not the time to "sit on the sidelines."
A candidate's shortcomings, he said, "are no excuse for inaction." Describing what people are hearing as part of a "great national debate" he asked the students for their vote and told them they should have no qualms about voting for Trump.
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