What determines whether your ad appears above the organic results or in the right hand column?

Generally the number of total ads, but occasionally, chance.

The highest bid, or the best quality score will appear on the top and a lot of times above the serps and then other ads will most likely appear in the right column.

If you want the top spot put the bid high and choose position preferences..

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I believe the OP is talking spatially, not in terms of order.

Is there a place in Adwords to choose position preference? i want my ad to appear directly above the organic results, NOT on the right hand side of the page.

Refer back to my original response. There is not, as far as I know, a way to control this, but ads #1-3 will have a higher probability of appearing on TOP of the organic search results spatially.

The more you bid and the higher your CTR the better your chance.

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I Smoke Pot and I Like it a Lot!

Turn on your position preference when setting up your campaign.

Setting in 1-5 position preference. Bid higher for the first time and see

whether your ads show up or not. If your ads show in the first page,

you can bid higher or get higher CTR to increase your ads position in

1-3 position. Usually ads in 1-3 position appear on top of organic

search result. I hope this help you!