* JPMorgan, United Technologies spark profit optimism

* Financials extend prior session's advance

* Oil rebounds after two days of declines

* Factory activity shrinks in U.S. Mid-Atlantic region (Updates to midmorning)

By Ellis Mnyandu

NEW YORK, July 17 (Reuters) - U.S. stocks were little changed on Thursday as a rebound in oil prices and weak regional economic data offset stronger-than-expected earnings from financial services companies.

Investors snapped up shares of embattled banks after JPMorgan Chase & Co's (JPM.N: Quote, Profile, Research) reported a stronger-than-expected profit a day after Wells Fargo & Co's (WFC.N: Quote, Profile, Research) results catapulted financial stocks to their biggest gains in nearly two decades.

But oil prices reversed two days of deep losses, sparking caution about inflation and consumer spending.

Shortly after the open, the Dow and the S&P 500 pared gains and the Nasdaq briefly turned negative following a report that showed factory activity shrunk in July in the U.S. Mid-Atlantic region.