When Donald Trump announced he was running for president almost a year ago, social media became inundated with jokes at his expense while experts struggled to take his campaign seriously.

But the billionaire became the presumptive Republican nominee Tuesday night after winning Louisana's primary, prompting Ted Cruz to drop out of the race.

He first announced he was running for president in June 2015 during a speech in New York City's Trump Tower.

'Trump faces an uphill battle to be taken seriously by his rivals, political watchers and the media,' the Washington Post predicted at the time.

Scroll down for video

Donald Trump first announced he was running for president in June 2015 during a speech in New York City's Trump Tower (pictured)

Just after Trump's announcement, the New York Times wrote he might be running for president just to further secure a spot in the limelight - and maybe promote his businesses.

'Mr. Trump's remarks in Midtown Manhattan were unlikely to allay suspicions that he is entering the race mainly to appear in debates and win attention from the media,' the newspaper wrote after Trump's announcement speech.

'He bragged extensively about the golf resorts he owns ('I have the best courses in the world') and a hotel he is developing in Washington.'

Nathan Gonzales, the editor of the nonpartisan Rothenberg & Gonzales Political Report, told USA Today at the time that Trump would turn into 'a big headache' for the Republican party.

'Donald Trump is not going to be the Republican nominee for president. Any time that he consumes on the debate stage and in the media is time he's taking away from a legitimate contender,' Gonzales said.

Comedian Stephen Colbert derided Trump's campaign, saying it would 'make late-night television great again'.

'I love Donald. You know, he looked great on television,' Colbert said. 'I was really surprised. He came out and I thought, "He looks like he fell into a river and they raked his body out of the surf down in Cape May three weeks from now," but the important thing is the crabs hadn't gotten to his eyes yet. And that sends a message of confidence to voters that if you vote for him, he's not physically dead.'

Experts said Trump (pictured arriving on his personal helicopter at the Iowa State Fair in August last year) would struggle to be taken seriously as a presidential candidate

The day after Trump announced he would run for president, reporter Chris Cillizza wrote on his Washington Post blog The Fix that the billionaire's goal was 'attention, not winning'.

He pointed out that Trump had a negative 42 favorability rating within the Republican party, saying this meant the billionaire was doomed to loose.

'You cannot and do not win anything when your numbers look like Trump's,' Cillizza wrote. 'I can't say it any more clearly than that. There's nothing you can say or do -- not that Trump would ever even consider going on an image rehabilitation tour -- to change how people feel about you. Republicans know Trump. And they really, really don't like him.'

Twitter users lampooned Trump's political ambitions too.

'If Donald Trump can run for president then so can my dog Lou,' one of them said, along with a photo of a dog sporting a side-swept hairdo similar to the billionaire's mane.

Another discarded Trump's candidacy as 'a Veep storyline that would have been discarded for being too absurd even for an HBO comedy'.

'Donald Trump announces this morning that he will run for president. His hair will announce on Friday,' one man quipped.

Another criticized the tycoon for referring to himself in the third person, comparing him to Gollum, the repulsive Lord Of The Rings character.

Twitter users lampooned Trump's political ambitions too. One of them said: 'If Donald Trump can run for president then so can my dog Lou' with a photo of a dog sporting a hairdo similar to the billionaire's mane

Another discarded Trump's candidacy as 'a Veep storyline that would have been discarded for being too absurd even for an HBO comedy'

Also poking fun at the billionaire's hairdo, one man quipped: 'Donald Trump announces this morning that he will run for president. His hair will announce on Friday'

Another criticized the tycoon for referring to himself in the third person, comparing him to Gollum, the repulsive Lord Of The Rings character

Two months later, Trump was leading most GOP polls but the Washington Post's Aaron Blake said it was too early to give credit to the numbers.

'Basically nobody who follows politics in any depth thinks either Donald Trump or Bernie Sanders could be elected our next president,' Blake wrote.

Making the case that neither Trump nor Sanders stood a chance, he added: 'And are Republicans who are terrified of another Clinton administration really going to nominate a candidate who is viewed unfavorably by two-thirds of the electorate, as Trump is?

'Are Democrats going to nominate a socialist with whom they might agree more than Clinton but who, well, is a SOCIALIST.

'The answer to those questions is almost definitely not.'

The Huffington Post made headlines at the time by relegating coverage of Trump's campaign to its entertainment section.

'After watching and listening to Donald Trump since he announced his candidacy for president, we have decided we won’t report on Trump’s campaign as part of The Huffington Post’s political coverage,' the website wrote at the time.

'Instead, we will cover his campaign as part of our Entertainment section. Our reason is simple: Trump’s campaign is a sideshow. We won’t take the bait. If you are interested in what The Donald has to say, you’ll find it next to our stories on the Kardashians and The Bachelorette.'

News about Trump's presidential bid has since appeared on the Huffington Post's politics section.

When the mogul seemed to struggle to keep up with his opponents during GOP debates, the New Yorker saw it as a sign he had 'no plan for a second act' after the initial excitement of his campaign.

'The struggle of the second act in a political campaign, as in any drama, is that the problem identified at the beginning—the one that seized our attention—must be translated into the more mundane tasks that propel the protagonist toward his or her goal,' Washington correspondent Ryan Lizza wrote.

'Won’t even the most committed Trump supporter start to wonder why this self-proclaimed savior hasn’t prepared himself to answer standard policy questions?'

That fall, opinion writer Dana Milbank pledged in the Washington Post to eat his own column if Trump became the nominee.

'I’m so certain Trump won’t win the nomination that I’ll eat my words if he does,' Milbank said. 'Literally: The day Trump clinches the nomination I will eat the page on which this column is printed in Sunday’s Post.'

Trump remained in the race and in January 2016 Vox editor-in-chief Ezra Klein imagined a scenario in which the billionaire lost the election.

'Trump could just ... not win. He could lose the Iowa caucuses. He could fall short in New Hampshire,' Klein wrote in a post titled 'Here's what I think Donald Trump's loss will look like'.

'A loss in any early state might lead to a loss in every state. Losing a presidential primary is often like going bankrupt: It happens slowly, then all at once.'

Trump did lose the Iowa caucus in February but won the New Hampshire primary with 35 per cent of the votes.

He has secured 1,047 delegates, far ahead of John Kasich's 153.