Small business owners first crippled by the economic downturn and then further encumbered by a tight lending environment in its aftermath are set to hire more workers, make more capital investments and are reducing their retirement savings targets this year as they set their sights on growth and expansion.

According to American Express OPEN's Small Business Monitor survey released Thursday, 35% of small business owners with less than 100 employees plan to hire new workers this year, the highest level since the fall of 2008.

Of those companies looking to hire, 35% expect to add at least two employees and 20% plan to bring on four or more new workers.

While the respondents' macroeconomic perspectives are decidedly more optimistic than they've been in the past two or three years -- 37% expect to grow their sales and profits this year while only 18% characterize their businesses as in "survival" mode -- the one nagging issue keeping them up at night remains cash flow and, just as important and directly related, their access to capital from lenders.

The survey found that 66% of the 728 small business owners queried are concerned about cash flow, an all-time high in the bi-annual survey's history, up from 60% in the fall of 2010 and 53% in the spring of 2010.

"With the desire to scale a business comes the willingness to make the tough financial decisions necessary to achieve that goal,” Susan Sobbott, President of American Express OPEN, said in the report. "Business owners have sacrificed cash flow comfort in order to make the switch from survival to growth mode."

Twenty-nine percent of respondents said it has become more difficult to access capital over the last six months, despite the efforts of some banks to pump more cash back into the hands of small business owners through a variety of methods including carrying the paper on real estate loans from smaller regional banks.

Still, 23% said the cash-flow squeeze was making it tough for them to pay their bills on time, acquire new customers (14%) or even meet their payrolls (7%).

Faced with these cash-flow issues, perhaps it's no surprise then that among small businesses, accountants and bookkeepers will be the first new employees they hire (14%) followed by a social media specialist (9%) and then either an advertising or marketing staffer (6%).

From a 32,000-foot perspective, small business owners said the greatest threat to the U.S. economy's nascent recovery the deficit (26%), followed by unemployment (22%), government regulation (18%), oil prices (16%) and the housing market (6%).

After enduring this brutal stretch and, in many cases, either losing a sizeable portion of their own personal investments or tapping into their retirement savings to stabilize their flagging businesses, small business owners are more concerned about their ability to comfortably afford retirement.

Eighty-one percent of respondents said they're now worried about their ability to save for retirement, up from 74% in 2010, and 34% characterized themselves as "very worried."

These small business owners now on average estimate they'll need $1.2 million to comfortably retire, down from the $1.28 million they estimated in 2007 and one in four believe they'll need less than $750,000 socked away to enjoy their golden years in style.