The real battle, of course, is in Uttar Pradesh. From the reports and hearsay, here is what I have gathered. BSP and SP are in tough fight for first place, with both expected to get 120-130 seats. In essence, the BSP is expected to lose about 90 seats from its 2007 tally. These spoils are what everyone is going after. BJP and Congress are in race for 3rd and 4th place, with both hoping to get in excess of 75 seats so they can then decide who forms the government.
Things could still change dramatically. In UP, caste matters more than anything, and there is a lot of attention all the parties are paying to their candidates and campaigners to ensure the right math. It is a seat-by-seat fight.
On election day, what will make all the difference is the get-out-the-vote operation. In a four-cornered contest (not counting the smaller parties who are also in the fray), victory margins are going to be wafer-thin, so that party which does a better job of getting its supporters out to vote will have a significant advantage.