The gentleman above would deserve reps for one month straight for having sound reasoning at the base of his post....
Now let me state the reasons as why Madara would win this fight despite all the odds,and apparently I'me the only one who actually is going to elaborate on the battle,the rest of the responses were "the 5 kages win" with no evidence or explanation whatsoever.
Hashirama<Madara-he's actually the guy who will give Madara more problems
Tobirama<Madara-he's nearly irrelevant as he showed basically a couple of Suitons and nothing more,basically he can't compete with what Madara has showed.
Hiruzen<Madara-I don't buy the Prime Hiruzen horsecrap,as I've never seen him,not even once in the manga.So Old Hiruzen gets fodderized by Madara
Minato<Madara-His only relevancy in this fight is as a support role,because he lacks the firepower to harm Madara,his rasengan would be laughed at.The best option for him and Hiruzen to win is the Shiki Fujin.And his speed won't be much of relevance either as his Hiraishin would be rendered nearly useless by the forest rising of both Madara and Hashirama.
Tsunade<Madara-she will be the healer of the team,and can provide excellent support like Katsuyu,to stall Madara for precious moments,moments which could dictate the loss of the fight from the win.
If the Kages want to win they need not to rely on raw power as they're in lack(ironically it is so) but on teamwork.
Problem is that Madara has been fighting nothing more than double,triple,quadruple teams from the moment he awakened from "sleep",so it would be quite and ordeal to land a single clean hit on him(if he is fighting seriously that is).He parried a punch from Tsunade that appeared from thin air,and couldn't possibly fathom she would be there,but still f***g parried,same ting he did with the Raikage,he parried a sucker punch while not even looking in the same direction of the attacker.
Basically Madara has monstrous reflexes.
Now Madara seen has he is outnumbered,he would opt for his 25 clones,which revert the numbers back on his side.
So it's basically 26 Madara vs 5 Kages.
According to the Databook in regards to the Moku Bunshin it states :
Wood Clone Technique (木分身の術, Moku Bunshin no Jutsu)
Ninjutsu, Kekkei Genkai, No rank, Supplementary
User: Yamato
The protean Wood Clone, reflecting one's whole soul!!
A clone created by altering one's own cells with chakra. It has more endurance than the normal Shadow Clone and doesn't disappear when hit by the enemies attack. Moreover, since it has the ability to merge with plants and trees, it is also great reconnaissance missions!!
Do you see people it'a gonna be be 26 replicas of the guy who is playing with 5 kages in the canon.
Do you understand how broken the guy is? I guess even Kishimoto must feel bad for going overboard with this character
Damn think of it as 20 clones dropping 2 meteors each,that's 40,the 5 remaining spam Magatamas and katons,then the real Madara activates Izanagi and awaits for the carnage brought by 40 asteroids collapsing on mother earth