T-SQL (SS2K8) :: XML Export From A Denormalized Table

I have a de-normalized table that I need to export to XML using For XML, but put all of the related rows under the same node.The table is alot more complicated than the example below, but for proof of concept purposes, i'll keep it really simple:

Campaign, Price
C1, 4.00
C1, 6.00
C1, 10.00
C2, 1.00
C2, 13.00
C3, 20.00

If I have a table of campaigns and prices, I would like to output it as XML like the following:

<Campaign name="C1">
<Price value="4.00"></Price>
<Price value="6.00"></Price>
<Price value="10.00"></Price>
</Campaign>
<Campaign name="C2">
<Price value="1.00"></Price>
etc

The default behaviour gives me this:

<Campaign name="C1" price="4.00"/>
<Campaign name="C1" price="6.00"/>
<Campaign name="C1" price="10.00"/>

Is there an existing option that deals with this automatically, or do I essentially need to do a group by to output the campaign element, and then union an ungrouped select to output the price element?