He was the senior guy, so I didn't want to be harping about rules.

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Yet Mr Obama has been harping on about raising taxes on the rich since his first election campaign.

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This situation can partially be attributed to financial services and marketing companies harping on the financial aspects of retirement.

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Combined with Mr Lieberman's harping on religion and morality, this has given the Gore ticket a double appeal to the middle class.

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But aren't you doing the same thing by then harping on it rather than moving on to something that you could actually try to pass legislatively?

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Although not harping on the role of the FDA, it is clear from the analysis that pretty much the entire collapse was due to delayed product approval.

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Finally, Romney gets an F for harping on energy independence.

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This time around, she said, the pundits are harping on divisions that she says are relatively mild by the standards of GOP schisms in 1976 and Democratic divides in 1980.

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Conservatives are often criticized for harping on family values, but what many of the critics fail to acknowledge is that strong, healthy families are essential for a strong, healthy economy.

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Harping on history might work, up to a point.

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Mike, you keep harping on your successes.

FORBES: Dow Jones Interactive