The attribution gadget is a gadget present at footer of blog and says "Powered by Blogger".The gadget is locked,when you click on the edit link of attribution gadget you will notice that there is no Remove link,Because the gadget is locked officially by the blogger.To unlock the gadget follow my below easy steps carefully. remove it.
I will show you how to remove it with ease.
THE FIRST THING TO DO IS TO BACK UP YOUR TEMPLATE IN CASE ANY MISTAKE HAPPENS YOU CAN ALWAYS GO BACK TO THE ORIGINAL TEMPLATE YOU USED.
CLICK ON THE LINK BELOW TO SEE HOW TO BACKUP YOUR TEMPLATE
How to Backup and restore your Blogger Template
Steps To Remove Attribution Widget on Blogger Blogs
1) Go to Blogger Dashboard => Template tab => Edit HTML tab (New Blogger Interface) or Go to Blogger Dashboard => Design tab => Edit HTML tab (Old Blogger Interface) and click on Expand Template Widgets check box
2) Search for the code below in your template. Use ctrl + F to locate it
<b:widget id='Attribution1' locked='true' title='' type='Attribution'>
3) Once you find the attribution code, change “true” on locked to “false” as shown in the image below

4) Save your template.
5) Go back to Design => Page Elements to check your success. The widget lock command has been disabled, so you can now move, edit and remove the widget.

6) With the remove button available, you can now remove the attribution widget from your blog.
OR
1. Go to Template ==> Edit HTML and and click on Expand Template Widgets check box
2. Click Ctrl+F and search for Attribution1 in your templates.
3. Then you should see some like the one shown below in your template:
<b:section class='foot' id='footer-3' showaddelement='no'>
<b:widget id='Attribution1' locked='true' title='' type='Attribution'>
<b:includable id='main'>
<div class='widget-content' style='text-align: center;'>
<b:if cond='data:attribution != ""'>
<data:attribution/>
</b:if>
</div>
<b:include name='quickedit'/>
</b:includable>
</b:widget>
4. Remove all the code except the one you see in red.
Finally, view your blog and see the changes. That’s all.