President Obama’s approval rating is just 40 percent in the 60 most vulnerable Democratic House districts, and at 46.6 percent nationally. History tells us when a president is below 50 percent nationally, his party loses more than 40 seats. Republicans only need to pick up 40 seats in the House and 10 in the Senate to take control. And it can be done. In 1994, Republicans gained a net total of 54 House seats, eight Senate seats and a majority of governorships.

So it won’t be a big surprise if Democrats, particularly in swing districts, prefer for Obama to stay in DC come fall.

But Bill Clinton will likely be in huge demand, as will Sarah Palin, his Republican counterpart, who has become a heavyweight endorser as well.

For someone who no longer holds elective office and has been summarily dismissed by the press, Palin has an impressive endorsement record this primary season; she’s 9-3 so far. Among her best picks: state Rep. Nikki Haley (SC) and Carly Fiorina (CA).

An interesting title match in the fall elections: Who will have more impact as the party surrogate? Sarah Palin or Bill Clinton? Texas may be one of the races to watch with the Clinton-endorsed former Houston Mayor Bill White (D) challenging Palin’s pick, incumbent Gov. Rick Perry (R).