Even for France, this may scare off too many voters in what may turn out to be a close election. The current income top tax rate is 40% in France, though there is also the "wealth tax" that can add a few points for wealth (house, possessions) above €790,000. There are also the usual sales taxes (VAT is around 20%) plus social taxes (retirement, health insurance) that can add up to another 12% at the high end.
It's possible to enact such tax increases but unlike the US where citizens are taxed (or at least must report their income, then pay if above an annual amount) French citizens simply have to leave the country. Over the years, many have done this, including celebrities and bankers. It's easy enough to pass such a tax increase but if nobody is there to fund pay it, it's meaningless. It would have made a lot more sense to propose an increases that targeted the super-rich, that yes, do indeed exist in France.
If the Socialists want to regain the presidency, they're going to need to be more thoughtful. The current president is a very beatable candidate but if they go off message, something that seems to be the case here, they will struggle. Most people understand that the existing model needs to be modernized and the super-rich are lumped in with the rich, but this surprise may require additional thought. Repealing the Sarkozy tax cuts would have been fine and acceptable for many people. Raising taxes to help the country during a tough economic time would also be sellable. But throwing out a surprise increase of 35% across the board for everyone at the high end is poor planning.
Maybe Hollande was only referring to the super-rich, but if that was the case, he needed to get his messaging clear before the announcement. This is no longer the blowout election that was predicted last year when Strauss-Kahn was the leader of the left. BBC News:
The Socialist favourite in France's presidential election, Francois Hollande, has said top earners should pay 75% of their income in tax. "Above 1m euros [£847,000; $1.3m], the tax rate should be 75% because it's not possible to have that level of income," he said. Speaking on prime time TV, he promised that if elected, he would undo tax breaks enacted by Nicolas Sarkozy.