Mark Cuban and Gennifer Flowers at center of debate guest dispute while Trump chief denies investor linked to Russia talks is part of official campaign

The US presidential election turned into an increasingly dirty fighting on Sunday, as polls presented the gap between Hillary Clinton and Donald Trump tightening ahead of their first broadcasted debate.

Trumps campaign manager did not rule out the prospect of the nominee getting personal onstage at Hofstra University in New York by summoning the ghosts of Bill Clintons sex life, insisting that the Republican nominee had a right to defend himself.

The two camps traded threats over who would be in the debate audience. After Clintons team confirmed that it had offered a front row seat to billionaire Trump critic Mark Cuban, Trump responded that he might invite Gennifer Flowers, a former model who had an extramarital encounter with Bill Clinton in the 1980 s.

On Sunday, Clinton campaign chair John Podesta described Trumps reaction as to dive in the sewer and go for a swim, although the Republican nominees running mate, Mike Pence, denied that Flowers would be present.

Bob Schieffer, a venerable broadcaster who has moderated presidential debates, commented on CBS: Those kinds of things are beneath the dignity of the office that these two people are running for. I think they both would do well to think about that.

The shadow boxing came as a Washington Post/ ABC poll put Clinton only two points ahead among likely voters, 46% to 44%. A survey by the Morning Consult website gave Trump an edge of one point.

The debate on Long Island is predicted to draw an audience of 100 million, a record for a political event. National security will feature among the topics. Many are intrigued by the prospect of car-crash television and just how ugly things might turn. Online fact-checkers and a vast following on Twitter are likely to play a major role in real time in shaping the narrative of victory and defeat.

On NBCs Meet the Press on Sunday, host Chuck Todd wondered if the aim of inviting Cuban, who has questioned Trumps fiscal worth, was to get under Trumps skin.

Podesta responded: No, I believe Mark Cuban is one of the business leaders who was never involved in partisan politics whos endorsed Hillary because he guesses shell do better for the economy. I think that, you know, you watched[ Trumps] reaction, which is to do his favorite athletic, whose purpose is to dive in the sewer and go for a swim.

On Saturday, Trump tweeted: If dopey Mark Cuban of failed Benefactor fame wants to sit in the front row, perhaps I will put Gennifer Flowers right alongside of him! Blooms herself then tweeted: Hi Donald. You know Im in your corner and will definitely be at the debate!

On Sunday, his allies sought to defuse the issue. Vice-presidential candidate Pence told Fox News Sunday: Gennifer Flowers will not be attending the debate tomorrow night. Donald was use the tweet yesterday truly to mock an effort by Hillary Clinton and her campaign to truly distract attention from where the American people are going to be focused tomorrow night, which is on the issues, its on the choice that we face.

Trumps campaign manager, Kellyanne Conway, told CNNs State of the Union she could not confirm that Flowers would attend.

I cant believe how easily baited the Clinton campaign was, she told. Basically, Mr Trump was saying, Look, if Mark Cuban is going to send out these texts that say the humbling at Hofstra and this is his big downfall, then Mr Trump was putting them on notice that we could certainly invite guests that may get into the head of Hillary Clinton.

But we have not invited her formally and we dont expect her happening there as a guest of the Trump campaign.

One of the debates numerous subplots will be the question of whether Trump might be provoked into lashing out, perhaps by tackling Clinton with her husbands past infidelities in a bid to humble her. It would be a risky move for the tycoon, himself thrice married.

Conway told: He has a right to defend themselves against anything that Secretary Clinton may say in response. Theres no plan to do that. Im not going to disclose what we have been doing in our debate dialogues. But the fact is that he has every right to defend himself.

You know, hes always, constantly attacked, and then the moment he counterpunches, then people are just shocked that he would do that, he would try to defend himself.

But he will answer the questions, as we certainly said he hoped that the issues to go to policy. Answer those issues that the American people have. They deserve and expect these candidates to be talking about the issues.

Clintons campaign manger, Robby Mook, told the same show: Nobody knows which Donald Trump is going to show up to this debate. And, in fact, his erratic temperament has been a subject of quite a bit of discussion and I would argue its why hes not fit and prepared to be president.

Coming 56 years to the day after the first presidential debate, between John F Kennedy and Richard Nixon, Mondays battle appears set to be the most unpredictable and potentially the most brutal ever held. Clinton is a seasoned politician who has been preparing with taunt debates reportedly featuring her aide Philippe Reines in the role of her foe. Trump is a brash businessman and Tv showman who lunged insults at his foes during the Republican primaries.

On CBSs Face the Nation on Sunday, Paul Ryan, the House speaker who, as Mitt Romneys running mate, debated Joe Biden in 2012, advised Trump: Over-prepare. Look, Hillary Clintons been doing this most of their own lives. She is the consummate pro. This is new for Donald. So I think he should patently over-prepare for it.

And the thing I believe, plainly I prepared for these myself. You have to offer the country a vision, go on offence, prosecute your instance, hold your foe accountable. But then depict the country the direction you want to go and prepare, prepare, prepare. And I hope hes doing that.

On Sunday morning, Trump gratified Israeli prime minister Benjamin Netanyahu at Trump Tower in New York City. Netanyahu was due to meet Clinton afterward.

A Trump campaign statement said: Mr Trump acknowledged that Jerusalem has been the eternal capital of the Jewish people for over 3,000 years, and that the United States, under a Trump administration, will finally accept the long-standing Congressional mandate to distinguish Jerusalem as the undivided capital of the state of Israel.

Carter Page, whom Donald Trump has named as a foreign policy adviser, speaks at the World Trade Center in Moscow. Photo: Dmitry Serebryakov/ TASS

Trump could face difficult questions from Clinton, and indeed debate moderator Lester Holt, over his business ties to Russia and repeated kudo for its president, Vladimir Putin. Conway tried to distance her nominee from an adviser reportedly under investigation for sessions with senior Russian officials. She denied that Carter Page, an energy investor whom Trump named as an adviser earlier this year , now had any contact with the Trump campaign.

This week, Yahoo News, quoting US intelligence sources speaking on condition of anonymity, reported that Page was under investigation for private communications with senior Kremlin officials about the possible lifting of economic sanctions. The Guardian could not independently confirm an investigation.

Its on our radar screen, the site quoted an official as saying. Its being looked at.

Earlier this year, Trump named Page specifically as one of five foreign policy consultants. Last month, campaign spokesperson Hope Hicks called Page an an informal consultant named as part of a much larger group several months ago.

Speaking to CNN, Conway strenuously repudiated any links to Page, who worked in Russia for Merrill Lynch from 2004 to 2007 and subsequently founded an energy company and has argued against US sanctions on Russian officials.

Hes not part of our national security or foreign policy briefings at all, certainly, Conway said. Hes surely not part of the campaign that Im running. We have a number of people, fabulous people. Hes not among them at Trump Tower.

Conway did not deny that Page may have communicated with Kremlin officials, who have been accused by some US officials of attempting to meddle in the American presidential election. A hack on the Democratic National Committee, for example, was traced by independent security firms to Russian security services.

If hes doing that, hes certainly not doing that with the permission of the campaign, Conway said. Hes surely not authorised to do that.

Clintons campaign has released an ad connecting Trumps refusal to release tax returns a break with 40 years of election tradition with possible business interests in Russia. The Trump Organizations significant ties to foreign businesses could create numerous conflicts of interest for a Trump White House, though it remains unknown what keeps Trump has in Russia, if any.

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