The head of the Republican Party predicted on Tuesday that if Donald Trump continues to use a 'measured' tone on the campaign trail, he will be tied nationally with Hillary Clinton – or beating her – in less than two weeks.

Reince Priebus, chairman of the Republican National Committee, told reporters on a conference call that Trump has made 'very prepared, mature comments on the campaign trail,' and claimed voters are watching the GOP nominee 'and saying "You know, I can see him in the White House".'

'I think people want to buy the change product,' Priebus said, hinting at the party's characterization of Democratic nominee Hillary Clinton as a stale status quo politician. 'I think that's what both parties saw all year.'

'But it's going to be important for us and for Donald Trump to continue down this measured path that he's on,' he cautioned. 'And if he does that, I think he's going to be tied, or ahead, at or just after Labor Day.'

Republican National Committee chairman Reince Priebus told reporters on a conference call Tuesday that the presidential race is narrowing, and Donald Trump will be tied with Hillary Clinton or beating her by Labor Day

Trump is trailing in almost all recent polls but Priebus praised his more 'measured' tone on the campaign trail

'I think you see on the national level, you see some of the national polls narrowing,' Priebus declared. I think some of the state polls are narrowing. I saw a good poll in Iowa the other day. I think Ohio was narrowing.'

The last national poll that showed Trump leading Clinton outright was a CNN/ORC survey in the fourth week of July.

One poll released this week, from the Los Angeles Times, showed the two tied, but every other poll in August has given Clinton an edge.

She leads Trump by 5.5 percentage points in an average of polls compiled by Real Clear Politics.

A Trump spokesperson did not respond to an inquiry about whether or not his campaign shares Priebus's optimism about near-term polling.

An average of national presidential polls conducted this month shows Hillary Clinton leading Trump by more than 5 percentage points

Clinton has few opportunities to shore up her polling advantage in the next two weeks, with just one speech and no other public events

Clinton has planned only one public event during the next two weeks, a speech on Thursday that promises to be an all-out assault on Trump's alleged coziness with the 'alt-right' movement, a conservative fringe that embraces a white supremacist 'race realist' philosophy.

Aside from that one address, however, her entire calendar through Labor Day consists of fundraisers that are closed to the public and the press.

Clinton has been hit with a torrent of speculation about her health and her physical readiness to occupy the Oval Office, both online and from Trump advisers including former New York City Mayor Rudolph Giuliani.

On the question of how Trump will recover from the growing public perception that he has softened his iron-clad tone on deporting illegal immigrants by the millions, Priebus was noncommittal on Tuesday and pointed toward a forthcoming Trump speech that's still being written.

'Obviously it's a major issue that both campaigns are confronting,' he said. 'I would suspect that he's going to clear up any of these questions very shortly.'

'I think we're gonna wait and see what he's going to say on the subject.'