ANALYSIS-Small bank share offers may find fewer takers

* Small banks seen raising capital to plug shortfalls

* Fewer options for smaller banks to raise capital

* Unsuccessful capital efforts may cause bank failures

By Tenzin Pema

NEW YORK, May 27 (Reuters) - Raising billions of dollars may have proved easier than expected for big U.S. banks seeking to shore up their balance sheets, but smaller institutions may find filling holes in their capital structure an uphill battle.

Regional banks and other smaller institutions that did not undergo the "stress tests" that the 19 largest U.S. banks recently faced may have fewer options to raise money.

"The people that run money in this world have had their fill of bank equity at this point," said Michael Cohn, chief investment strategist at Atlantis Asset Management in New York.

"There's more than enough Wells Fargo, Citi and Bank of America to fill everybody's coffers -- so why would I take a risk on some small bank when I could own Wells Fargo." Smaller banks may have a far greater need for capital relative to their size and may need to tap equity markets to cover losses on everything from home mortgage loans to commercial property lending and credit cards.