THE US: President Bush and Senator Kerry were back in Ohio this week, no surprise to the local population. This vital swing state has seen 20 presidential visits since Mr Bush took office, with six visits in the last six months, compared to 12 by Mr Kerry.
The candidates are also spending more on advertising in Ohio than anywhere else except Florida, and Mr Bush has sent 50,000 volunteers into the state to add to the already strong Republican presence.
Ohio is so important because it carries 20 electoral votes, a large chunk of voting power that exceeds anything else in the swing mid-west states. Political experts also say Ohio is a microcosm of the voting patterns of the US.
In 2000, Mr Bush won by 3.6 per cent after Mr Al Gore stopped advertising in the state during the last few weeks of the election.
This time the Democrats are throwing everything they have into Ohio, most noticeably in the 29 Appalachian Mountain counties along Ohio's border with Kentucky, West Virginia and Pennsylvania. This economically depressed region, with a Democratic majority but a strong religious Republican base, could be the key to the entire election if Mr Kerry carries Florida.
According to Mr Joe White, director of the Centre for Policy Studies at Ohio's Case University, Appalachia could go either way. It tends to be more attracted to the fundamentalist religion and social issues of the Republicans but the economy is in a dire state. "It's almost like West Virginia. There are gold and coal mining areas and there are really depressed former industrial areas."
The other key area for Democrats is north-east Ohio, home of the state's heavy industry, where the Democratic-leaning unions are strong.
According to Mr Alexander Lamis, politics professor at Case University and author of Ohio Politics, north-east Ohio has remained solidly Democrat since the manufacturing unions swung to the party during Franklin D. Roosevelt's New Deal.
"You also have a large black population in the north-east of the state. Cleveland has a majority black district in one area. In the small rural towns in the middle of Ohio, you don't have that at all. It's also a culturally liberal area of the state, much more so than Cincinnati."
Cincinnati, which was visited by Mr Bush and Mr Kerry for a veterans' conference this week, is strongly Republican and almost certain to remain so in this election.
According to Prof White, this voting tradition began with anti-slavery German immigrants, who flooded into the city in the mid-19th century and remained solid Lincoln Republicans. The Republican vote increased as the city became relatively affluent.
Cincinnati is also on the border with Kentucky, and is heavily influenced by the southern Christian Republicans.
"There is a lot of Dixie in Cincinnati and that's good news for President Bush," says Prof Lamis.
The cattle and corn farm belt in the middle of the state is also strongly Republican, although even within farming country, some poorer counties swing to the Democrats. The Democrats also have the cities of Toledo, which is strongly Democrat, and Dayton, which is a Democrat swing city.
"The thing to remember here is that the Republicans have a strong party machine in Ohio, whereas the Democrat Party more or less imploded a decade ago," says Prof White.
This has led to a virtual Republican monopoly on state politics, with control over the governor's office, the Supreme Court, the major state jobs and both houses of the state assembly.
"Looking at that, you might think that it's a Republican state, but that's not true at all," says Prof Lamis. "We don't know yet who is going to win Ohio because we don't know what the national dynamic will be, but if Kerry is going to win, he is going to win with Ohio."
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