BOSTON (AP) -- Democratic Senate hopeful Elizabeth Warren is faulting U.S. Sen. Scott Brown for opposing a measure that would have ended $4 billion in tax subsidies to oil companies.

Brown sided with fellow Republicans and four Democratic senators in voting against the measure. Two Republicans -- Senators Susan Collins and Olympia Snowe of Maine -- backed the measure.

Warren campaign spokeswoman Alethea Harney said Brown was "helping the richest, most profitable companies in the world" get billions of dollars in tax breaks and loopholes.

Brown spokesman John Donnelly said Brown opposed the measure because it would do nothing to reduce rising gas prices at the pump.

President Barack Obama has argued that Americans are getting hit twice -- once at the pump, and once by sending billions of dollars in tax subsidies to oil companies.

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