BATON ROUGE, La. — After lagging in polls, Republican U.S. Rep. John Fleming thinks he’s found his path to the runoff in Louisiana’s U.S. Senate race, positioning himself as the grown-up among the major GOP candidates.

In his latest TV ad released statewide this week, Fleming slams the two leading Republicans in the race, U.S. Rep. Charles Boustany and Treasurer John Kennedy, as the equivalent of junior high school students.

The 30-second spot shows adults at cafeteria tables throwing food at each other, while a narrator says: “It’s like a junior high food fight. First, Boustany attacks Kennedy as a wasteful spending liberal. Then, Kennedy attacks Boustany on character.”

Fleming’s campaign sees the squabbling and attacks between Boustany and Kennedy as peeling support from both and giving Fleming an opportunity to overtake them in the Nov. 8 election.

A Minden doctor in office since 2009, Fleming suggests he is “fighting the real enemy,” which the commercial says is President Barack Obama and Democratic presidential nominee Hillary Clinton. The ad aligns Fleming with Donald Trump, the Republican presidential nominee who is expected to win Louisiana’s electoral votes.

The race to fill Louisiana’s Senate seat — open since Republican David Vitter isn’t seeking re-election — is expected to be decided in a December runoff between the top two vote-getters in November. With 24 candidates, a few percentage points could be all it takes to edge out a competitor.

The most recent independent poll in the race, by Southern Media and Opinion Research, showed Fleming running fifth among candidates, behind Kennedy, Boustany, Democratic lawyer Caroline Fayard and Democratic Public Service Commissioner Foster Campbell.

But it also showed a race largely up for grabs, with more than a quarter of voters surveyed still undecided.

Kennedy and Boustany have been running as though they’re the only contenders in the race, ignoring other Republican contenders and letting the Democrats battle among themselves, even though everyone runs together on the same ballot.

Among the spats, Kennedy’s campaign has circulated allegations published in a new book, which cites unnamed sources, that Boustany was involved with prostitutes who were later killed. Boustany has called the allegations “despicable lies” and has blamed Kennedy for widening the reach of the information.

Fleming’s campaign says its polling shows the race tightening. Spokesman Matthew Beynon said Thursday the campaign is spending about $350,000 a week on TV advertising and will stay on the air until the election.

“Voters are just now getting to know John Fleming, and as his statewide name identification has risen, voters are now moving to his campaign,” Beynon said in a campaign memo.

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