REDWOOD CITY, Calif. (AP) - President Barack Obama's campaign is ramping up criticism of Republican Mitt Romney's record in Massachusetts, while the Republican nominee is contrasting his business record with the Obama administration's economic performance.

Romney told donors Wednesday night that his old company, Bain Capital, initially invested just a few million dollars in the office store chain Staples before it began to thrive. He compared that with the $535 million in loan guarantees the Obama administration gave the green energy company Solyndra before it went bankrupt last year.

Romney planned a campaign appearance in northern California Thursday morning.

Meanwhile, top Obama strategist David Axelrod planned to appear in Boston to criticize Romney's record as governor.

Axelrod says Massachusetts' economy was "close to the bottom of all the states" when Romney led it.

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