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I see that you have already added a log in your form. Anyways, to answer your question, yes it is possible, you could try adding a cover image instead. Please see our guide here: http://www.jotform.com/help/75-Customize-your-Form-using-Custom-CSS-Codes.
Or you could use the image field found under the Form Tools.
It's easier to use this so that you could position the image more appropriately instead of using CSS code, although, you could also use that instead.