http://en.wikipedia.org/wiki/Petro_PoroshenkoDespite being one of the richest ukrainians, didn't stain his reputation with any corruption schemes.
Was in several governments, including the last one of Mykola Azarov, yet, again, didn't take part in any scandals, doubtful decisions, etc
Ideological position ? (Left/center/right? Moderate/radical?)
Center moderate.
Supported maidan from the very beginning, but always called for peaceful actions, asked protesters to refrain from violent actions.
Even was nearly pelted with stones on 1st December by right sector on Bankova street when he tried to stop them.
What does he wants for Ukraine as a whole?
He didn't publish his election program yet, so no details here, but when he talk about future of Ukraine he mostly uses words democracy and freedom of speech.
Your personal opinion on him?
Obviously he is very smart guy and experienced politician and economist, probably even honest, so I'm quite optimistic about him, especially compared to second probable candidate Tymoshenko.
On other hand Yushchenko made more or less the same immersion before the president elections in 2004 and proved to be complete disappointment. However Yushchenko's biggest fault was that he was spending too much resources on "national identity" and sometimes on supporting nationalists, and not enough on economy, which was already far from good back then.
Not something you could accuse Poroshenko in.
why do you think he will be elected, and why not the others?
His ratings speaks for himself. He had three times more support than Tymoshenko even before last events when Klitschko withdrew from elections and supported him instead.
Basically he is the only real candidate.
Tymoschenko has bad reputation, she was prime minister before and didn't do good, too much populism, popular but wrong decisions.
Dobkin and Tihipko are members of Party of Regions which is still associated with Yanokovich, there is no way one of them could win.
Tyahnybok and Yarosh are radical nationalists, and despite what russian media says, they don't have big support.
You can see their ratings here
http://en.wikipedia.org/wiki/Ukrainian_presidential_election,_2014