The fact that Macron is hanging on to a runoff by his fingernail tips just shows how weak the pro EU center-to-center-left is right now. Considering he has practically no competition for his niche, he should probably be in the thirties, at least.
Macron is running as a complete upstart with no party organization and an overwhelming majority of voters having never heard of him before a couple of months ago. To be honest, in my opinion, there's no reason why he should be doing as well as he is.
Also, the last time a "Centrist pro-EU" candidate made it to the second round (not runoff) was 1981 with Giscard, although the comparison of their economic liberalism are somewhat different.
Considering he has practically no competition for his niche,
i am not sure if the EU topic is the most important point of this election inside of france.
Also, this is correct. The French are much more concerned with sclerotic growth and an "erosion of values," whatever that means.