WASHINGTON — Sen. Pat Toomey (R., Pa.) and Democratic challenger Katie McGinty traded attacks Monday over who supports corporations and who would help regular people, engaging in another front in their neck-and-neck race.

The two candidates held competing media calls, with McGinty blasting Toomey's opposition to the Consumer Financial Protection Bureau — the federal agency meant to protect consumers from financial abuses — and Toomey accusing McGinty of supporting "corporate welfare" because she favors rules that require ethanol to be used in gasoline.

The political scuffle begins on territory where Democrats hope to wage the campaign: They have spent months bombarding the airwaves with TV ads painting Toomey, a former derivatives trader, as an ally of Wall Street banks, and brought in Sen. Elizabeth Warren (D., Mass.) to hammer that point home at a Philadelphia rally Friday.

Toomey tried to flip the attack by charging McGinty with helping big agri-businesses.

The Democrat began the exchange Monday morning, pointing to the Consumer Financial Protection Bureau's recent role in punishing Wells Fargo for creating more than two million bank and credit card accounts without their customers' knowledge in order to collect added fees. The bureau, a brainchild of Warren created in response to the 2008 financial crisis, fined Wells Fargo $100 million.

"He's working overtime to knee-cap the organization that has been standing up for innocent people," McGinty said in her call. "What we see here is just further evidence that Pat Toomey made his millions on Wall Street and though he changed his title to senator, he still goes to bat for those banks."

Toomey, in a separate call a short time later, indicated in response to a question that he would like to see the bureau dismantled, along with many of the Dodd-Frank banking reforms passed in the wake of the financial crisis. He has criticized those laws as overly burdensome on businesses.

The bureau, he said, is a "very ill-conceived and badly governed entity that is not accountable to anyone."

He  said it does not have a bipartisan board overseeing it and its budget is not approved by Congress, giving lawmakers little power to check the bureau's actions — something that chafes its critics, but that supporters laud as a way to maintain the agency's independence.

"It doesn't have a proper governance structure, nor is it subject to proper oversight of Congress," Toomey said. "That's a very bad way to run an organization that has enormous power."

Toomey has sponsored measures to give Congress control of the bureau's budget and to put a bipartisan oversight board in place. Republicans say that would make the agency accountable, though Democrats argue it would let politicians hamstring the bureau.

Toomey assailed McGinty for backing the federal ethanol mandate — which requires refineries to include ethanol in gasoline. He said ethanol is expensive for businesses and consumers, and harmful to the environment, while helping corn producers.

He called the law "another example of how Katie McGinty loves to pick these corporate welfare programs."

Toomey noted a recent report that Philadelphia Energy Solutions, a major East Coast refinery, is looking to cut workers and expenses, blaming the ethanol mandate, low fuel prices and high inventories.

McGinty, a longtime environmental official in Washington and Harrisburg, has favored using ethanol as a way to reduce the U.S. dependence on foreign oil.

Her campaign accused Toomey of hypocrisy on "corporate welfare" — citing his long-standing support for cutting corporate taxes and his votes for Republican budget proposals that would have extended existing tax breaks that benefit the oil and gas industry.

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