5 Things That Ultimately Doomed Marco Rubio's Presidential Campaign

— -- Marco Rubio was once the dubbed "The Republican Savior," but on Tuesday he suspended his campaign after a devastating loss in his home state of Florida. What went wrong?

The son of a bartender and a maid -- both Cuban immigrants -- Rubio was young, charismatic, a great speaker with a compelling personal story. After a disappointing showing among Hispanic voters in 2012, Rubio’s background seemed a particularly good fit for 2016.

After a meteoric rise in Florida politics, Rubio rode the Tea Party wave to the Senate in 2009. And during his presidential campaign, Rubio himself repeatedly made the case that only he could unite and grow the party. In short, his campaign seemed to have many of the right ingredients for success. But after his loss Tuesday, his White House hopes were quashed.

Here are the top five things that ultimately doomed his campaign:

1. The 'Rubio Robot' Moment

It was an attack he should have seen coming a mile away. During the ABC News debate in Manchester, New Hampshire, in February, Chris Christie, who had been going after Rubio for weeks, again argued the Florida senator was too young and unprepared to be president.

Rubio refused to engage -- he tried to pivot and attack Obama instead. In doing so, however, Rubio began repeating the same lines.

“Let's dispel with this fiction that Barack Obama doesn't know what he's doing. He knows exactly what he's doing,” Rubio said again and again.

Christie pounced on Rubio for his "memorized 25-second speech." Rubio ended up repeating the same line, almost verbatim, four times.

The candidate who had always been praised as a great speaker was now being called robotic. Over the next few days -- the days leading up to the New Hampshire primary -- it was all Rubio would get asked about. What happened? Did he freeze? How was he not better prepared to fight back? Twitter was abuzz. Rubio even had people dressed as robots come troll him at various campaign events.

Without a doubt, the meme slowed Rubio’s momentum from Iowa and contributed to a disappointing fifth place finish in the Granite State.

2. The Personal Attacks

Rubio spent most of his campaign trying to stay above the fray, arguing he wanted to run a campaign his children would be proud of, one that was worthy of the office he was seeking.

He spent the summer avoiding Donald Trump, only commenting on his inflammatory rhetoric when specifically asked to respond. Even on policy, it would sometimes be days before Rubio would comment. He argued if he spent all his time responding to what Trump was saying, his entire campaign would be consumed by it. Trump never really went after Rubio, so Rubio stayed away.

It wasn't until the heated GOP debate in Houston that Rubio would truly engage. He called out Trump for not having outlined any specific policy proposals. The field had winnowed down enough, his advisors said, that only now did it make sense to take on Trump.

The day after the debate marked a shift in strategy for Rubio. All of a sudden, he began mocking Trump's misspelled tweets, his hair, his tan. He even suggested Trump had wet himself at the debate. Asked about Reagan's 11th commandment, which states Republicans shouldn't attack each other, Rubio shot back that it didn't apply to Trump.