Capital One (NYSE:COF) has been steadily expanding its presence in the banking industry, aiming to compete more directly with the country’s

U.S. banking regulators said on Friday they approved Capital One's $35.3 billion purchase of Discover Financial Services , paving the way for the combined firms to become the nation's eighth-largest bank.

Two regulators signed off on the $35 billion deal, which the banks say will create a competitor to Visa and Mastercard. But consumer advocates warn that the deal may raise costs.