Bye Bye Sarko, Bonjour Hollande

His defeat was predicted since for months, if not years, but despite having all the odds against him, it his defeat was is far from being overwhelming.

Hollande said once that if Sarkozy was a bad president, he was however an excellent candidate.

As a native English speaker, I would use the world "nevertheless" rather than "however"

That's true, and he would have been re-elected if Sarkophobia hasn't become that important among the population.

I would probably write "Sarko-phobia" and hyphenate "re-elected"
"had not" rather than "hasn't"

Never a president will have been as im unpopular as him.

Never before has a president been as unpopular as him.

(I wonder if it's possible to say "he" instead of "him"?

certainly, if you said it this way, for example: "Never before has there been as unpopular a president as he was."

I looked for answers and natives seem divided on the question.)

It just depends upon how you wish to say it...natives will disagree on usage! :)

Now a new presidency begins with the "normal" Hollande.

You might mean (rather than "the normal") to better say:
Suggestion: "Now a new presidency begins with the more conventional candidate, Mr. Hollande."

He is not very charismatic, but many of his rivals, or ex-rivals (once one is elected president, one certainly has discovers many friends), say realize that they underestimated him.

This is awkward and could be written as two sentences to improve it.

I don't think he is going to change our lives, nor that he is going to solve all of the problems that France and Europe face.

Presidents, even though they have a lot of power in France, are no not magicians.

People often believe that a new president is a wizard and who can do whatever he wants.

They end up disappointed, and then vote for far-right or far-left parties, although they know that the proposals of those parties are utopic. utopian

The real question is: will Hollande be able to do what he wants with the current crisis?

Even if I'm against austerity, some of the spendings spending he proposes don't doesn't seem wise to me.

I'm not an economist though, and even economists don't agree disagree on those these subjects.

We will vote to elect the numerous deputies, 577 to be exact, who will often appear to sleep (when they're not absent) on the upon parliament benches when they are not absent. of the Parliament.

Too bad that he doesn't want to cut reduce their number.

Little question: when one says "someone" or "one", is it then better to say "they" or "he or she"?

Someone or one is singular. You can use he, but in this age of political correctness, sometimes people go out of the way to say "she."

Like in the following sentence: "if someone has a question, they (or "he or she") can ask me".

he or she could be used. They is used, but it sounds colloquial to me personally.

Which one is more formal, and which one is more used used more frequently?

Answer: he or she, in that order.

His defeat was predicted since months, if not years ago... / His defeat had been predicted since months, if not years before...

Hollande said once that if Sarkozy was a bad president, he was [however] an excellent candidate.

Or, "that although..."

That's true, and he would have been reelected if Sarkophobia hadn't become that important among the population.

Future: Never again will a president be as unpopular as him. / Past: Never before had a president been as unpopular as him.

(I wonder if it's possible to say "he" instead of "him"?

I'm not sure! You could certainly say "as he was," though.

I looked for answers and natives seem divided on the question.)

I'll look it up later and see if I can find anything.

We don't need to see him everytime and everywhere [and all the time].

Here, "all the time" can be omitted since its meaning is understood from "everywhere." "Every time" makes no sense without something to modify it, like "every time we turn on the TV," for example.

Even if I'm against austerity, some of the spending / some of the expenditures he proposes don't seem wise to me.

I'm not sure about "spendings," usually I only hear it in the singular in political contexts: "government spending." Also, the opposite of "expenditures" would be "cuts" (reducing expenditures in specific areas).

Everyday speech or writing: If someone has a question, they can ask me. / Formal writing (Canadian English): Anyone who has a question can ask me. / If there are any questions, I'll be happy to answer them. (etc.)

It's always better to use "they" if you're speaking or writing in an informal context. That's what most people do. On the other hand, some linguists don't accept "they," so if you're writing in a formal context and you're accountable to someone, like a boss or teacher, you should find out what they want! The standard procedure in Canadian English, as far as I know, is to avoid such situations completely by rephrasing the sentence. In other words, if you are writing in formal English and you encounter such a situation, you should rephrase the sentence so that there's no need to use a pronoun.

Which one is more formal, and which one is more used?

"They" is by far more used in everyday communication. The major problem with "he or she" and such constructions is that they sound horribly awkward. They're redundant, and if you have to repeat the expression several times within a paragraph it becomes a pain to read. That's why "they" has become mainstream, but apparently some linguists don't like it. I think those linguists are just old-fashioned. :)

We got rid of the little thug at last. / At last, we got rid of the little thug.

I'm (so) relieved because, like a lot of the* French, I was fed up with him and his government. *plural

His defeat was predicted for months, if not years, but despite having all (the) odds against him, it was far from an overwhelming failure / a staggering failure / a crushing loss.

Hollande once said that if Sarkozy was a bad president, he was, still, / nonetheless, / however, an excellent candidate.

It turned out to be true, and he (probably) would have been re-elected if Sarkophobia hadn't become so popular among French citizens.

Never before had there been a president as unpopular as him (him = Sarkozy). / as he (had been). "he" might be possible if you mean to refer to him as the object ~ roughly translates to "He had never before been seen (by the French) as such an unpopular president."

Now, a new presidency begins with the "ordinary" Hollande.

He is not very / particularly charismatic, but many of his rivals, or rather ex-rivals (once president, one certainly accumulates many friends quickly), says that he had underestimated him. / He is not brimming with charisma, but...

I'm not against a normal / ordinary president anyway.

We don't need to be seeing him all the time and everywhere / and all over the place.

I don't think / I doubt if he is going to change our lives, nor that he will solve all of the problems that France and Europe face.

Presidents, even though they have a lot of power in France, are not magicians. your original is not grammatically correct but works in casual conversation

People often believe that a new president is a wizard with the ability to mold any situation into whatever he wants.

They end up / They wind up disappointed, and then vote for far-right or far-left parties, although they know / although they are well aware that their proposals are purely utopic.

The real question is: will Hollande be able to do what he wants (to) with the (current) crisis?

Even if / though I'm against austerity, some of the spending measures he is proposing don't seem wise (to me).

I'm not an economist though, but even economists disagree on the same subjects.

The legislative elections are in a month. / The next round of elections will be held in a month.

We will vote to elect the numerous deputies, 577 to be exact, who will just sleep (when they're not absent) on the benches of the Parliament.

Too bad that he doesn't want to cut their staff.

Small / Little question: when one says "someone" or "one", is it then better to say "they" or "he or she"?

For example, in the following sentence: "if someone has a question, they (or "he or she") can ask me".

Which one is more formal, and which one is more commonly used?