With polling places opening in less than 24 hours — and many votes already cast in Florida's primary — it's unlikely a candidate like Pam Keith, a Democrat running for U.S. Senate, has made her case in time to put a dent in the competition, even if she was the first in the race.

Keith, a South Florida lawyer and well-traveled former naval officer, is in a multi-way primary for the seat, her major competition being Congressmen Alan Grayson (D-Orlando) and Patrick Murphy (D-Jupiter). For the majority of the primary run-up, media have treated the race as a two-way contest between Grayson and Murphy.

But that's changed some in the past week or so — though probably not enough to spell victory for for Keith, who has even called herself a long-shot candidate.

For many Florida Democrats, it's a choice between two flawed candidates. Grayson has been subject to a string of controversies, from ethics questions to domestic abuse allegations. Earlier this year, Murphy was busted embellishing his resume — that, after the Democratic party's progressive wing for months criticized the former Republican for siding with Republicans on issues like Keystone XL.

Murphy is a mild-mannered establishment favorite, Grayson is a fiery progressive.

Keith is also something of a progressive, though a life steeped in military service and corporate law has given her an understanding of conservative viewpoints — something she sees as an asset. In debates, she's civil, poised and amiable.

“You cannot keep sending millionaires to Washington and then be surprised that the policies that come out create millionaires. You cannot keep sending [corporate executives] to Washington and then be surprised that all the policies that come out favor corporations,” Keith said at a Tampa candidate forum last month, one at which she was the only candidate to show up. “You want someone in Washington whose heart you trust.”

In a surprise move earlier this month, the Miami Herald endorsed her, citing her "engaging personality and a world view that cuts through that political fog."

"Everywhere I've gone, I've been the new kid, the one who has to make the overtures, the one that has to make new friends. And so you learn how to build bridges. You have to or else you live in isolation," she told WFSU.

Keith’s top priorities, if elected to the Senate, include criminal justice reform and gun control — at one local event she even floated the idea of requiring the military to buy weapons only from manufacturers that don't sell assault rifles to civilians. She's also passionate about reforming the Department of Veterans Affairs.

“Currently, the VA makes a veteran prove every aspect of their claim. If any piece of their documentation is missing, they need to resubmit it over and over again… That is completely wrong-headed,” Keith said. “My proposal is to put the burden of proof on the VA. If a veteran puts in a claim that he's 60 percent disabled, the VA has 90 days to disprove it. If they cannot disprove it, then it is taken as true and the claim is paid.”

If elected, Keith would be just the second African-American woman ever elected to the U.S. Senate, after former Illinois Senator Carol Moseley Braun.

The winner of Tuesday's Senate primary will likely face incumbent Republican Sen. Marco Rubio in the general.

Zebrina Edgerton-Maloy contributed to this report.