It is possible, that Newt is playing the old rope a dope by acknowledging his past two debates were lack luster.
The perception was that Obama was shit scared to debate Obama when Newt was the king of the debate stage, but Newt hasn’t been performing as of late and Obama could get cocky.
Should Obama actually challenge Newt to a debate, I believe Newt would slay him.
Should Obama balk at a debate, I think Newt is wise to hound Obama at campaign stops with rebuttals.
I think he is just trying to lure Obama into a debate, making Obama think he is weak.
Incumbents generally don't ask for debates, they grudgingly agree to them, and have the upper hand in setting ground rules. The challenger is usually lesser known, so the debates give the challenger an opportunity for exposure the incumbent would rather not give him.