Following the weekend's primaries and the upcoming votes on Tuesday, many eyes remain fixed on a presidential candidate who has been highly touted, but has delivered few victories, leading to concerns about his campaign's viability.

Florida U.S. Senator Marco Rubio, a candidate lauded as the future of the Republican Party, has failed to break through in this election cycle. As more critical elections approach, the senator could be left questioning the justification for his campaign.

On Super Tuesday, Rubio won his first contest of 2016, the Minnesota Caucuses, a state only one GOP presidential candidate has won since 1960, more than a decade before the senator was born.

Over the weekend, the Rubio campaign easily prevailed in the Puerto Rico Republican primary, but it was in a territory which has no electoral votes in the general election. So through more than twenty contests, Rubio has won only two and they are two that the GOP can hardly point to as evidence that he can deliver states to Republicans that could not or would not be won by Donald Trump or Ted Cruz.

Rubio's reportedly surprising third place finish in the February 1 Iowa Caucuses catapulted his campaign, but led to only a fifth place finish in New Hampshire following a week of effusive media coverage.

Despite the underperforming results, Rubio attempted to allay his critics and bolster his supporters over the weekend.

"This map only gets better for us," he said ahead of his Puerto Rico victory. "We're soon gonna be in the winner-take-all process . . . that's where we feel very confident as we move forward."

On Tuesday, Hawaii, Idaho, Michigan, and Mississippi hold primaries and caucuses and all proportionally award delegates. The following Tuesday, March 15, six more states and territories vote, of which four states (and the Northern Marianas) follow the winner-take-all format.

Of those four winner-take-all states (Florida, Missouri, Illinois, Ohio), Trump leads handily in three of them. According to the Real Clear Politics polling averages, Trump even leads Rubio in the senator's home state of Florida by 16-20 points. Ohio remains the tightest of these four where Trump leads Ohio Gov. John Kasich by five in the latest poll while Rubio is in fourth.

The rationale of a successful Rubio campaign has long been a theme in the media, both the mainstream and its alternatives, but has shown few signs of achieving reality. Rubio has suffered from a long list of liabilities, including but not limited to a campaign that notoriously refused to engage in the retail politicking necessary to succeed in the early states.

As of this writing, the delegate count has Donald Trump with a lead of 384 delegates to Ted Cruz's 300. With only half as many delegates as the second place Cruz, Rubio is currently third with 151. As high stakes contests come in the winner-take-all format -- which do not currently appear to favor him -- Senator Marco Rubio will likely be faced with crucial questions about how long his presidential campaign can continue.

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