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You may have heard the old politician's advice to vote early and often. People in Florida have a chance at least to vote early. And many did cast their votes long before last night's debate. That may be a problem for Newt Gingrich, whose support in Florida was not very strong until recent days.
NPR's Greg Allen reports from Miami.
GREG ALLEN, BYLINE: Newt Gingrich, Mitt Romney and Rick Santorum are blanketing the state with rallies and personal appearances. The airwaves are full of campaign ads. But Jeanne Casserta has heard enough. With several days left to go in the campaign, she stopped by the library in Coral Springs this week, to cast her vote for Mitt Romney.
JEANNE CASSERTA: I think basically, I don't need to listen to any more speeches. So I just had to follow who I think would be the strongest person to win the primary.
ALLEN: It's easy to cast your vote early in Florida elections, and an increasing number of voters are doing so. In most counties, polls opened last Saturday and close tomorrow. Well over 100,000 people have already voted early that way. Another popular way to vote early is through an absentee ballot.
BRIAN HUGHES: These days, calling it absentee is almost a misnomer. It's almost better to call them vote-by-mail.
ALLEN: Brian Hughes is a spokesman for Florida's Republican Party. Because of Florida's liberal absentee ballot rules, anyone who chooses can mail in their vote. Three hundred thousand Republicans cast absentee ballots in the 2008 primary and this year, Republican voters are expected to surpass that. Hughes says it's a sign Florida Republicans are energized - in part, because of the state's early primary.
HUGHES: We're a much bigger prize in the early landscape - as we always wanted to be. So you know, like they say: Florida, Florida, Florida.
ALLEN: In Florida, working the early and absentee vote has become an important tactic, even for campaigns at the county commission level. Brett Doster, a Florida Republican strategist working with the Romney campaign, says in primary campaigns, absentee and early voters are critical.
BRETT DOSTER: Primary elections are lower turnout, so that the more votes that you can track - or the more likely votes for your candidate that you can track, and get in the bank through the absentee ballot program or the early voting program, ensures you a greater possibility for success on Election Day.
ALLEN: And this is an area in which Mitt Romney has an advantage. Lists of all those who request absentee ballots are available to the campaigns. The Romney campaign began working in December, to follow up with mailers and phone calls. By the time the Gingrich campaign turned its attention to Florida, more than 100,000 ballots had already been returned. When primary day rolls around next Tuesday, more than a half-million Floridians - maybe a quarter of the estimated turnout - are likely to have already voted. That's enough to sway an election.
Doster says the case study for this was in the 2008 Republican gubernatorial primary in Florida. [POST-BROADCAST CORRECTION: NPR incorrectly referred to the year of the Florida Republican gubernatorial primary. It was 2010, not 2008.] That's when Florida Gov. Rick Scott was a political newcomer. In the primary, he edged out the establishment candidate, Bill McCollum.
DOSTER: Bill McCollum actually won a plurality of votes on election day. But Rick Scott had beaten Bill McCollum in the absentees and the early vote. And he ultimately was the winner of that primary. So that gives you a good empirical example of how important that early vote is.
ALLEN: In that race, as in this one, people who vote early are not influenced by last-minute revelations, or momentum shifts, that sometimes change the course of campaigns. At an outdoor coffee stand in Miami this week, I ran into Mario Lazo(ph). He's a Republican who says he likes the convenience of voting early, and used to do it. But given the volatility of recent elections, no longer.
MARIO LAZO: No, no, no, no. I learned that from my wife. It makes sense to me. I say well, let's go vote early. And she says no, no, no. And she was the one who enlightened me on that.
ALLEN: But among Florida voters as a whole, the popularity of early and absentee voting still appears to be growing. A survey conducted by the American Research Group found that at the beginning of the week, 17 percent of likely Republican primary voters had already cast ballots. Within that group, Romney has a 7-point lead over Gingrich.
Greg Allen, NPR News, Miami.