Democrat Liz Mathis has banked more early votes than Republican Cindy Golding for Tuesday’s special election in Iowa Senate district 18, and a survey by Public Policy Polling puts her narrowly ahead in the final days of the campaign.

Click here for PPP’s full polling memo, including the questionnaire and cross-tabs. Tom Jensen posted highlights here. Mathis leads Golding by 52 percent to 46 percent, even though respondents split 44 percent to 44 percent on whether they would prefer Democrats or Republicans to be in control of the Iowa Senate. High name recognition from local television work and a strategy to avoid taking a stand on controversial issues are probably helping Mathis outperform the desire to maintain a Democratic-controlled Senate.

Public Policy Polling surveyed 878 “likely voters” in Iowa Senate district 18 between November 4 and November 6. The margin of error is plus or minus 3.3 percent. I inquired about the likely voter screen; PPP responded that they pulled a list of voters who had voted in at least one of the last three general elections, and the call script began by asking respondents to “hang up now” if they were not planning to vote on Tuesday.

Opponents of same-sex marriage rights slightly outnumbered supporters by 46 percent to 42 percent, but only 11 percent of respondents told PPP that gay marriage was the most important factor determining their vote.

Both President Barack Obama and Governor Terry Branstad are in net negative territory among this poll’s respondents. Obama’s approve/disapprove numbers were 37/51, even though 51 percent of those surveyed said they had voted for Obama in 2008, compared to 43 percent who said they had voted for John McCain.

Branstad registered 39 percent approval and 42 percent disapproval. I am surprised that 18 percent of respondents were unsure whether they approved or disapproved of the governor’s performance. Remember, this wasn’t a survey of adults or registered voters in Senate district 18. This poll tried to sample likely voters in a special election for the state legislature. Presumably we’re talking about a very politically engaged slice of the electorate. Yet nearly a fifth of them don’t have an opinion on Branstad’s work as governor.

I don’t know how to interpret that finding. Maybe Branstad has done a good job of pushing his political agenda below the radar, or maybe voters aren’t sure what Branstad’s been trying to do, because the 26 Iowa Senate Democrats kept many of his proposals from becoming law.

Share any relevant thoughts in this thread.