Small business owners are quickly losing faith in the current slate of presidential nominees.

So says online lender OnDeck in its second survey of business owners about the presidential primaries, published on Wednesday. About 34 percent of business owners do not have faith in the presidential contenders, an increase of nine percentage points compared with a similar survey OnDeck conducted last fall.

Given the carnivalesque atmosphere of the primaries, where debates have at times descended into vulgar mudslinging contests, the results hardly seem surprising. So who do entrepreneurs think represents them best? Donald Trump received 37 percent of the vote, followed by Bernie Sanders with 28 percent. Hillary Clinton came in third with 16 percent.

It turns out that many small business owners are nostalgic for former president Ronald Reagan, with 42 percent saying he has been the best friend to entrepreneurs in recent memory. Bill Clinton followed with 17 percent, and President Obama came in third with just 14 percent. 

OnDeck found that the most critical issue for small business owners is economic growth, which two-thirds of respondents noted (up from 56 percent in the company's October survey). Tax policy was second, with 46 percent of the vote. Health care costs came in third, chosen by more than a third of business owners polled.

One takeaway from the survey is that candidates ignore small business owners at their peril. Ninety percent voted in the 2012 election, and 95 percent are registered voters, OnDeck reports. About one-third made donations in the last presidential election, and so far one-quarter have done so during the current presidential cycle.

"Given their active participation in past presidential elections, candidates would be wise to engage this vast voting constituency of 28 million small business owners," James Hobson, chief operating officer of OnDeck, said in a statement.

For the most recent survey, OnDeck surveyed 531 small business owners via Facebook between February 29 and March 14.