Iowa voters remain divided on the issue of gay marriage, a new poll released Wednesday concluded.

According to a Public Policy Polling (PPP) survey of 668 registered voters taken July 5-7, 47 percent support the state's law on marriage, while 44 percent do not.

In April, Iowa celebrated the fourth anniversary of the unanimous Iowa Supreme Court ruling which legalized gay nuptials in the state.

Twenty-six percent of respondents said that its legalization has had a negative impact on their lives, compared to 11 percent who said it has had a positive impact.

A February 2012 Des Moines Register poll found greater support among Iowans (not registered voters). In that poll, 56 percent of adults said that they were opposed to a constitutional amendment defining marriage as a heterosexual union, while 38 percent favored such a ban.

PPP pollsters also found disappointment with Republican Governor Terry Branstad's job performance by a 46-45% margin. However, Branstad continues to fare better than his possible Democratic challengers.