Latest Iowa poll shows dead heat between Obama, Romney

(CNN) -- A new poll of likely voters in Iowa shows the presidential race is locked up between Mitt Romney and President Barack Obama.

The poll follows two others released in the last two weeks, one showing Obama with a slight advantage within the survey's sampling error, and another that put his advantage just outside of the sampling error.

Obama was at 49% and Romney at 45% in the new Des Moines Register poll released Saturday evening. Their margin is inside the poll's sampling error of plus or minus 3.8 percentage points.

The poll notes that only 2% of likely Iowa voters remain undecided, although 10% told pollsters they currently have a preference between the candidates but could be persuaded between now and Election Day to switch their support.

The CNN Poll of Polls for Iowa, which averages together recent nonpartisan, live operator polls of likely voters in the state, shows Obama at 50% and Romney at 44%. The Poll of Polls includes the latest Des Moines Register poll, plus samples conducted since September 16 by NBC News/Wall Street Journal/Marist and American Research Group. It has no sampling error.

Iowa has received its share of attention from the presidential candidates harkening back to its party caucuses, where the first votes this cycle were cast.

Obama has made 13 visits to the state this election cycle, while Romney has made 10 this year.

The state is one of nine toss-ups on the CNN Electoral Map and has six electoral votes.

GOP vice presidential candidate Paul Ryan will turn his attention to the state next week when he kicks off an Iowa bus tour hitting several cities in the eastern portion of the state.

Early voting in Iowa began Thursday.

The Des Moines Register Poll was conducted between September 23 and 26 and included 650 likely voters out of a larger group of 800 Iowa adults.