The Shulchan Aruch in Orach Chaim siman 126 discusses a shliach tzibur who accidentally skips ViLamalshinim, which makes him suspect to be a heretic for which we remove him from the amud.
The Mishna Berurah there #2 http://hebrewbooks.org/pdfpager.aspx?req=49623&st=&pgnum=294
discusses the other blessings which center around fundamental beliefs and why we don't suspect someone who skips one of those.
But he paraphrases a Yeshuos Yaakov and writes 'know that it is apparent according to everyone that if we (actually) know that a certain person does not believe in revival of the dead, or does not believe in the Final Redemption, and certainly if he does not believe in the heavenly origins of the Torah or in payment and punishment, according to all he is an Apikores and may not be the shliach tzibur. And if he takes the position by force, we do not answer amen after his blessings. And see earlier siman 53 siff 18'.
The Mishna Berurah is obviously ruling like this Yeshuos Yaakov. I'm pointing this out to clarify before I quote his words.
The words of the Yeshuos Yaakov can be found here http://hebrewbooks.org/pdfpager.aspx?req=9259&st=&pgnum=124 I will translate them.
'In the Yerushalmi it is explained that if he makes a mistake in 'Boneh Yerushalaim' and the bracha on 'Techias Hameisim' we remove him. This is not the opinion of our Shas (the Bavli). In truth though, it seems to me a Min is the name called to someone who does not believe in the reality of the singularity of God, and one who says Torah is not God given, and someone who does not believe in payment and punishment. These are the three first basic fundamental beliefs. As far as the other fundamentals explained in the Rambam, whoever denies them, even though he is a complete rasha, even still he is not excluded from being a member of this religion, as it says in the Seffer HaIkrim, first maamar. This was the reason to establish Malchios, Zichronos, and Shopharos. Malchios, for He is the singular KIng. Zichronos for payment and punishment. And Shopharos for Maamad Har Sinai, and Torah from Hashem. See there at length. Whoever believes in this is included in this religion. And certainly whoever does not believe in the other Ikrim or in any single idea from the Torah is a rasha who's punishment is great, even still he is included in the religion. Being included in the religion means he has a chezkas kashrus and therefore even if he makes a mistake in a different bracha for which we could assume he has machshavas chutz, since he says the blessing on the heretics and we see he is not a heretic, and included in the religious frame of mind, we keep him on his chazaka ans assume it was an accident or skipped 'Boneh Yerushalaim' by accident, but not God forbid that he has heretical ideas. But when he skips 'ViLamalshinim, and we suspect he has heretical thoughts, he has no chazaka, and we therefore suspect him of just that, and take him down'.
So there we have it. The Mishna Berurah quoting lihalacha the opinion of the Seffer HaIkrim as binding as far as being considered a Jew goes. And while it is true that one is a rasha if he doesn't believe the other Ikrim, at least he is included in the Jewish religion.
A final point, in light of the actual words of the Yeshuos Yaakov, the fact that the Mishna Berurah mentions techias hameisim is interesting, but can easily be construed to fit into gmul vi'onesh, payment and punishment. In fact it might even be a point of social commentary, where the Mishna Berurah went out of his way to mention a belief that was still wavering from the maskilim. In fact the Yeshuos Yaakov himself started his discussion by mentioning Techias Hameisim along with Boneh Yerushalaim, but later dropped Techias Hameisim and only focused on Boneh Yerushalaim, a bracha focused on the Ikar of the arrival of Moshiach, as seen in the Yerushalmi he is coming from.