New York: Facing sinking poll numbers and accusations of sexual assault, Donald Trump doubled down Monday on charges that the presidential campaign is being rigged, warning of "large scale voter fraud" in the US election.
With just three weeks to go in the rollercoaster presidential race, the brash billionaire Trump sharpened his message that the election system is plagued with deep problems, despite vehement denials by members of his own party.
The Republican nominee takes the stage Wednesday with his Democratic rival Hillary Clinton in their final debate.
But neither candidate has focused much on policy in recent weeks, as Trump intensifies criticism of the election system, raising concerns about possible post-election unrest should he lose.
"Of course there is large scale voter fraud happening on and before election day," Trump wrote on Twitter, without backing up his charge.
"Why do Republican leaders deny what is going on? So naive!"
In a series of tweets the previous day, Trump also railed against the media, as tensions mount ahead of the November 8 election.
"Polls close, but can you believe I lost large numbers of women voters based on made up events THAT NEVER HAPPENED. Media rigging election!" Trump wrote.
After the first debate, Trump said he would respect the election result. But he backtracked in an interview with The New York Times last month, saying, "We`re going to see what happens."
Trump`s running mate Mike Pence sought to ease tensions, insisting his camp would accept defeat if voters reject the Republican ticket at the polls.
"We will absolutely accept the results of the election," he told CBS Sunday.
One official who oversees election operations in his state, Ohio Secretary of State Jon Husted, a Republican, insisted Monday that Trump was being "irresponsible" for warning of voter fraud.
"If there is a systemic problem, please identify it. Don`t just make an allegation on Twitter. Tell me," Husted said on CNN.
"They`re not going to be rigged," he said of the election. "I`ll make sure of that."
Clinton`s campaign manager Robby Mook told reporters that Trump`s warnings about election rigging are meant to divert the public`s gaze from the candidate`s own shortcomings.
"He`s desperately trying to shift attention from his own disastrous campaign," Mook said during a press call on Monday.
"He knows he`s losing and he`s trying to blame that on the system. This is what losers do."
But Trump`s warnings may be having an impact.
A new poll by Politico and Morning Consult reveals that some 41 percent of voters believe the election could be "stolen" from Trump through massive voter fraud.
More than seven in 10 Republicans believe the election could be taken from them, while 17 percent of Democrats agree with the potential for serious ballot box fraud.
The poll of 1,999 registered voters was conducted October 13 through 15.
The nation`s top elected Republican, House Speaker Paul Ryan, who has declared that he would no longer "defend" the party`s nominee, rebuked Trump over his comments questioning the validity of the election process.
Ryan was "fully confident the states will carry out this election with integrity," his spokeswoman AshLee Strong said.Underscoring how divisive this election campaign has been, a Republican Party office in North Carolina was firebombed overnight Sunday, with the message "Nazi Republicans leave town or else" sprayed on an adjacent building.
No one was hurt in the attack, swiftly condemned by both candidates.
Two polls released Sunday -- taken after a slew of sexual misconduct allegations against Trump emerged last week -- put Clinton ahead.
The RealClearPolitics average of recent polls gave her a 6.3 percent advantage over Trump in a four-way race including third-party candidates Gary Johnson and Jill Stein.
Clinton is lying low ahead of the final debate, apparently relying on Trump self-destructing.
"She is trying to avoid issues for the next 22 days in the hopes that this will just end up being about Mr. Trump," his campaign manager Kellyanne Conway told CNN Monday outside of Trump Tower in New York.
Conway also added fuel to her boss`s contention that the election could be stolen.
"If there`s compelling evidence of voter fraud, obviously as early voting goes on... certainly we would take action," she said.
Trump who is heading to Wisconsin later Monday for a rally, is scheduled to hold two events Tuesday in Colorado.