TALLAHASSEE — The debate over debates is over.

Republican Marco Rubio and Democrat Patrick Murphy will finally stand face to face tonight in Orlando.

The one-hour debate will be held at the University of Central Florida and broadcast online and on certain TV and radio stations statewide. ABC chief White House correspondent Jonathan Karl will moderate.

In the first of at least two debates over the next three weeks, here are five things to watch:

1. Can Murphy win?

Six months ago, the 33-year-old Miami native was the odds-on favorite.

Back then, Murphy had raised nearly $8 million, had fresh endorsements from President Barack Obama and Vice President Joe Biden, and was looking at a group of little-known Republican challengers.

But in June, after pressure from Senate GOP leaders, Rubio announced he changed his mind and would seek re-election. Now Murphy is the underdog who spent much of the summer in a bruising primary where he defended his résumé embellishments. Since July, more than 25 public polls have been conducted. None show Murphy winning.

2. Does Rubio really want the job?

For more than a year, Rubio insisted to any reporter who dared ask that he wasn't seeking re-election.

"I have only said like 10000 times I will be a private citizen in January," Rubio wrote on Twitter in May.

Rubio gets to explain to millions tonight where he's at now. Murphy will surely remind the audience of Rubio's poor attendance record in the U.S. Senate and raise the larger question of whether Rubio really wants to represent Florida — or run again for president in 2020.

3. Presidential allegiance

Rubio is no fan of Donald Trump. During the presidential campaign, Rubio called Trump a con artist, a clown act, a lunatic and, in an ill-fated move, questioned the size of his hands.

And he took to Twitter to express outrage of Trump's comments on the Access Hollywood video. "No one should ever talk about any woman in those terms, even in private," Rubio tweeted.

Yet, Murphy is undoubtedly going to tie Trump around Rubio. How? Because the incumbent has continued to say he will support the Republican nominee. Unlike others in the U.S. Senate, Rubio has refused to unendorse Trump. Rubio's rationale is that Hillary Clinton is far worse for America.

Rubio is ready to return fire with anti-Clinton sentiment.

4. Is Murphy qualified?

As much as Murphy will question Rubio's work ethic, Rubio will likely waste no time bringing up discrepancies in Murphy's résumé and questions about whether Murphy truly has the professional experience to be a U.S. senator.

Since late May, media outlets have investigated inaccurate, and, at times, misleading claims Murphy has made. He embellished his academic degree from the University of Miami. But it's more complicated when discussing his claims of his having been a certified public accountant and a small business owner. Republican ads have labeled Murphy a liar, while Murphy counters that the attacks against him have all been "debunked." They haven't, but the nuances of those details get lost in the rhetoric.

Some of the Republicans' attacks — but not all, as Murphy asserts — have been rated "false" by independent fact-checkers, like PolitiFact. The nuances of Murphy's experience get lost in the rhetoric, but, nonetheless, the confusion makes for prime ammo.

5. How will they appeal to Hispanic voters?

In Florida, the large and growing base of Hispanic voters could prove to be kingmakers. Yet, both candidates are treading dangerous paths: Immigration activists are going after Rubio in radio ads, and Murphy made a politically risky call to end the embargo with Cuba.

Right now, Rubio appears to be leading among Hispanic voters. A Mason-Dixon poll conducted in late September shows him up 47 percent to Murphy's 40 percent.

To keep that lead, he'll have to contend with Trump's unpopularity with Hispanics, who favor Hillary Clinton over Trump 54 percent to 30 percent, according to an Associated Industries Florida poll.

Hispanics, and especially Cubans, could help propel Rubio to victory, but only if some of them are willing to split ballots for a Republican senator and a presidential candidate from another party. Similarly, Murphy will likely be trying to carry some of Clinton's support down ballot into the Senate race.

Times/Herald staff writer Michael Auslen contributed to this report.