House investigators have recommended that three lawmakers be further investigated to determine whether political contributions were improperly linked to votes on the huge financial overhaul bill.

The independent House Office of Congressional Ethics recommended that the member-run House ethics committee pursue potential rules violations by Republicans John Campbell of California and Tom Price of Georgia and Democrat Joseph Crowley of New York.

The ethics office recommended no further investigation of five other lawmakers in the same probe: Democratic Reps. Earl Pomeroy of North Dakota and Mel Watt of North Carolina, and Republicans Jeb Hensarling of Texas, Chris Lee of New York, and Frank Lucas of Oklahoma.

All offices of the lawmakers had received letters from the OCE by Tuesday and made the conclusions public.

President Barack Obama signed the financial overhaul bill into law July 21. It aims to restrain Wall Street excesses with the most sweeping overhaul of financial rules since the Great Depression, clamping down on lending practices and expanding consumer protections to address failures that precipitated the 2008 meltdown that knocked the economy to its knees.

The Democrats -- Crowley, Pomeroy and Watt -- voted for the final bill. The Republicans -- Campbell, Price, Hensarling, Lee and Lucas -- voted against it.

Campbell said he was "perplexed by OCE's decision, as they have presented no evidence that would suggest wrongdoing."

Campbell added that he "always complied with the letter and the spirit of the law. To suggest otherwise is unfounded and untrue. In addition, my voting record and opposition to a culture of taxpayer-funded bailouts has been and always will be unshakable."

Price said it was "truly a mystery" that his case was referred for further investigation.

"There being no evidence of any wrongdoing or any inconsistency in my policy position, one can only guess as to the motive behind their decision or even why they chose to initiate a review in the first place," he said. "My constant allegiance to a transparent and conscious divide between my official duties as a member of Congress and my actions as a candidate is without question."

Crowley's office said in a statement that he "has always complied with the letter and spirit of all rules regarding fundraising and standards of conduct."