In view of the many ups and downs in the U.S. presidential election campaign lately — a disastrous performance by president Obama in his first debate with Mitt Romney followed by an offensive rescue mission by vice president Biden in his debate with Paul Ryan — Tuesday evening’s second debate between Obama and Romney could be decisive.

Helped by Biden, who said everything to Ryan that Obama did not say but should have said to Romney, and who instilled new hope among despondent Democrats, Obama needs to step up and do well and, thereby, re-take the initiative and the lead in the polls that he lost after his debacle.

All indications are that the race has tightened and that Obama’s poor performance let Romney back in the race. But the polls also show that although the race is even nationally, it has not changed that much in the battleground states, particularly the key state of Ohio, where Obama still leads, although less so, by 2,2 percentage points according to RealClearPolitics. No Republican presidential candidate has ever won without winning in Ohio, so much depends on the Buckeye State and its 18 electoral votes.

The winner on November 6 needs a minimum of 270 electoral votes. In 36 of the 50 States, the outcome is already decided – Romney will win in 22 and Obama in 14. But since Obama’s victories will come in more populous state, he is ahead in the battle for electoral votes.

The outcome of the election will be decided primarily in nine states with a total of 110 electoral votes.FiveThirtyEight, the New York Times blog, recently described the situation in these nine states as following: Colorado (9) even; Florida (29) even; Iowa (6) leaning toward Obama; Nevada (6) leaning toward Obama; New Hampshire (4) probably Obama; North Carolina (15) probably Romney; Ohio (18) leaning toward Obama, Virginia (13) even; and Wisconsin (10) probably Obama.

On the betting site Intrade, 62.8 percent predict an Obama victory. Let’s see what they say after Tuesday’s debate!