By Roberta Rampton
MIAMI (Reuters) - Democratic presidential candidate Hillary Clinton, whose buoyant position in opinion polls has been threatened by a surprising new twist in the saga over her emails, on Saturday harnessed some celebrity star power she hopes will help win the battleground state of Florida on Nov. 8.
Musician and actor Jennifer Lopez headlined a free concert in Miami as part of a star-studded effort to get out the vote and energize volunteers.
"We're at a crossroads and we have to take the right road to the future," Lopez shouted to screaming fans in rain gear who danced through rain and a shower of red, white and blue confetti.
The concert provided some visual counter-programming to the latest email snafu to roil Clinton's race to win the White House.
The Federal Bureau of Investigation said on Friday it is investigating more emails as part of a probe into Clinton's use of a private email system - a late-breaking surprise that will likely continue to get extensive media play leading up Election Day.
Clinton's campaign has said she is taking the news in stride, and on Saturday she lashed out at FBI Director James Comey over the review.
The JLo event was the first of three high-profile concerts in states Clinton wants to keep from Republican rival Donald Trump, and it gave the former secretary of state a chance to connect with the key demographic of millennials she has sometimes struggled to reach.
"If we turn out, we win," Clinton told the crowd.
Celebrity-driven events like the concert "can serve as a bit of a distraction" from the controversy, said Eric Kasper, a political scientist at the University of Wisconsin-Eau Claire.
"It is a way to kind of take the edge off things because it tends to be more positive," Kasper said.
Next week, Clinton will take the stage with Jay Z in Cleveland, and then with Katy Perry in Philadelphia on Nov. 5.
A Harvard University poll this week showed that among likely voters aged 18 to 29, Clinton is leading Trump, a celebrity in his own right who starred in the reality television show "The Apprentice."
But turnout is a concern. The exceptionally negative tone of this year's race for the White House has turned off young Americans, Reuters/Ipsos polling shows.
Presidential candidates have long sought to create buzz with help from celebrity pals, said Tevi Troy, who chronicled the strategy in his book "What Jefferson Read, Ike Watched, and Obama Tweeted: 200 Years of Pop Culture in the White House."
"Campaigns do it to reach out to people who are not necessarily interested in politics but are interested in pop culture," said Troy, a presidential historian who worked in the George W. Bush White House.
The events are like a larger version of a campaign yard sign, a way to show a "groundswell" of support behind a candidate - and a way to appeal to fans of the musicians, Kasper said.
"It can create a kind of psychological connection that we otherwise might not have when a politician endorses a presidential candidate, for instance," Kasper said.
(Reporting by Roberta Rampton; Editing by Leslie Adler)