I use a wet washcloth and a bar of soap. Rub the wet soap bar right on the stain. Then use wet cloth to rub it off.
Hope you did not also get ketchup on it. Grease and tomato is a bad combination on any fabric.
karen

You should be okay with a mild cleanser. The great thing about microfiber is that it cleans up wonderfully. If you use resolve, do test a hidden area first. Allow it to dry before continuing to see how it does.

Here is a link that might be useful: carpet and upholstery cleaning