The Republicans will win back control of the House, and win enough Senate seats to equalize voting power (roughly 50-50). 

The purchase of the House will ensure Obama wins another term in 2012, contrary to the designs of Mitch McConnell:

‘The single most important thing we want to achieve is for President Obama to be a one-term president,’ says the Senate Republican leader.

The reason McConnell and the Republicans won’t be successful?  The problems faced by the US are structural, not cyclical, and election cycles are just too short and shallow to allow much headway in structural repairs.  By “structural” I mean, for example, that all the cutting around the margins won’t appreciably reduce the deficit a bit.   The only hope of balancing the budget is to decrease the promises of Social Security and Medicare/Medicaid, or vastly increase taxes.  Population growth won’t do it.  Economic growth won’t either.   But no one in government has the cojones to tell the American people the truth about the situation.   Structural deficits are just a symptom of bigger economic problems, none of which will be solved, or even can be solved, by imposition of government policies around the margins.  But that’s all our political system is capable of doing.  Perhaps democracy isn’t the worst government, except all the rest. 

So the only good it will do the Republicans to regain control of the House is that they can be the incumbents upon which the public will heap scorn when the next election cycle rolls through.

Obama in 2012.  The Tea Party has practically guaranteed it.