Iowans dont need to look at a calendar to know Election Day is near. They can just turn on the television.

Political ads for the presidential race are flooding this battleground state. Consider this: There were more presidential campaign-related advertisements on TV in the first five days of October than all of August, according to an analysis by The Gazette and several other newspapers.

Another fun fact: In September, there was an average of 1,858 presidential commercials a day in Iowa.

Thats ridiculous. Thats too much, Geary Zimmon, 23, a factory worker from Iowa City, said after casting his ballot in early voting last week.

The campaigns of President Barack Obama, a Democrat, and Republican nominee Mitt Romney  and their allies  appear to feel differently.

From late March through Oct. 5, there were 182,063 TV spots for the presidential campaign costing nearly $45.6 million that aired on network affiliates and the largest cable systems in eight Iowa markets. Smaller cable systems also are airing ads.

During that period, there were 101,882 commercials on behalf of Obama, versus 80,181 for Romney.

The Gazette reported last month that the partner newspapers counted nearly 100,000 commercials airing primarily from April through August.

An update of the following five weeks, Aug. 27 through Oct. 5, found that the volume had picked up as the presidential campaign approaches Election Day on Nov. 6.

Hover over each bar segment to see candidate specifics.

September saw 55,745 commercials in Iowa, more than double the August total of 23,338. In the first five days of October, 25,987 aired.

Iowa is one of about 10 battleground states expected to play key roles in selecting the winner in the presidential race. Those states also are where advertising has been concentrated.

Adam Vargason, 25, a tax accountant from Oelwein, said he doesnt watch a lot of traditional TV, but when he sees a political ad, It goes in one ear and out the other.

Voters may say that, but research shows that, in general, political ads work, said Dianne Bystrom, director of the Carrie Chapman Catt Center for Women and Politics at Iowa State University.

She is part of a national research team that has people watch political ads and measures the results. Based on studies through 2008, ads can cause people to change their assessments of a candidate, primarily on image but also issues, she said.

What we find is, even when they say that they hate them (ads), theres a movement in the needle, Bystrom said.

The effectiveness of ads may also have been evident in the lead in the polls Obama took last month, said Erika Franklin Fowler, co-director of the Wesleyan Media Project, which tracks political advertising.

In the last three weeks of September, Obama and his allies ran more ads than Romney and conservative groups in several battleground states, including Iowa, according to the Wesleyan Media Project.

In Iowa, ads on behalf of Obama outnumbered ads on behalf of Romney by 11,000 over the entire month of September, according to the Iowa newspaper analysis.

Theres reason to suspect that not only should the ads be working for those undecided voters, but also, if you have an imbalance (in the number of ads), that thats going to lead to one candidate doing better than the other, Fowler said.

Romney closed the gap in polls following the first presidential debate, and recent reports say his campaign and the independent groups backing him have stepped up their advertising.

This is a map of the major TV markets in Iowa. Click on one of the markets to see how many commercials have run, and how much money has been spent on behalf of both candidates in that market. The numbers listed are totals.

More than $1 billion is expected to be spent on TV advertising for this presidential election, which would be more than double than in 2008.

A look at one station puts the increase in perspective.

KCRG-TV9 ran 2,076 presidential-related commercials costing $925,900 from Aug. 27 through Oct. 5. In the same period in 2008, the number of commercials was 948, costing $243,550. The Gazette and KCRG-TV9 are owned by The Gazette Company.

The campaigns paid for most of the advertising in 2008. Outside groups like super PACs have proliferated since a 2010 U.S. Supreme Court decision known as Citizens United.

Its just light years different compared with 2008, said Steve Lake, senior manager of national advertising for KCRG-TV9 and The Gazette.

Local news is the most popular programming for political ad buyers, Lake said. Hit prime-time shows also are desired; right now Dancing with the Stars is a top choice.

And you can prepare to see even more ads in the homestretch of the campaign. KCRG-TV9 has oversold its inventory for Good Morning America for this week and next, and its local news programs are approaching capacity, Lake said.

Speaking with three weeks to go until Election Day, Cindy McDonald, a 42-year-old accountant from Cedar Rapids, engaged in some wishful thinking.

If I vote early, will it stop? she asked.The Gazettes Christy Aumer contributed to this report.