By Regis Duvignau and Bernard Grollier
CAMBO-LES-BAINS/SAINT-DENIS-DE-LA-REUNION, France (Reuters) - Francois Fillon's aides used an umbrella to shield him from eggs thrown by protesters in south-west France on Saturday as the beleaguered conservative fell further behind centrist Emmanuel Macron and far-rightist Marine Le Pen in opinion polls.
The contrast between former frontrunner Fillon, embroiled in a financial scandal, and new poll favorite Macron was striking as both candidates campaigned 29 days before the first round of France's unpredictable presidential election.
Addressing a rally in the French island of La Reunion, in the Indian ocean, Macron departed from typical campaign speeches by inviting members of the audience -- including a six-year old who asked him "How do you get to be president?" -- on stage to ask questions on a wide range of issues.
"It's historic, we need to decide whether we want to be afraid of the century that has just started ... or want to bring fresh ambition to France," the 39-year-old former investment banker said to chants of "Macron President!"
Macron, a former economy minister to Socialist President Francois Hollande, set up his own centrist party last year.
He has shot to first place in opinion polls since Fillon was put under investigation over suspicions he misused public funds by paying his wife hundreds of thousands of euros as a parliamentary assistant for work she may not have done. Fillon denies any wrongdoing.
Fillon slipped 2.5 percentage points on the week to 17 percent in a BVA poll published on Saturday, which saw Macron getting 26 percent of the first-round vote, up one percentage point from a week ago with Le Pen on 25 percent, down one point.
The number of undecided voters for the first round remains high, with 40 percent of voters still undecided.
The poll showed Macron winning a second round vote with 62 percent of the vote versus 38 percent for Le Pen, who is due to hold a rally in the northern France city of Lille on Sunday.
The poll was carried out partly before a TV interview on Thursday night in which Fillon, 63, accused Hollande of leading a smear campaign against him.
Met by some 30 protesters throwing eggs and banging pots and pans to shouts of "Fillon in prison" in the south-west France town of Cambo-les-Bains, Fillon told reporters: "Those protests are an insult to democracy ... the more they protest, the more French voters will support me."
Less than two weeks after revelations that Fillon had been given expensive suits as gifts, franceinfo radio said he had received two watches worth 12,000 and 15,000 euros from a businessman and a watchmaker. It quoted one of them as saying nothing was requested in return for the gift.
Fillon's team could not immediately be reached for comment.
Meanwhile, a faction of the centrist UDI party, which is allied with Fillon's The Republicans, was kicked out of the party on Saturday for rallying behind Macron.
The BVA poll also showed far-left candidate Jean-Luc Melenchon gaining ground in the first round, up 2 points from a week earlier to 14 percent, now 2.5 points ahead of the ruling Socialist Party's candidate Benoit Hamon.
(Additional reporting by Emmanuel Jarry and Andrew Callus; Writing by Ingrid Melander; Editing by Helen Popper)