Ko Min

A plugin to site owner to add voting functionality to the blog posts. 
Using the power of the ajax, voter can have instant voting and update to top voted widget. 
It doesn’t matter voter is logged in or not. Public voting is done by tracking their IP address. 
It isn’t end here. Blog owner will have complete control over those voting feature as well as using custom 
vote button and vote text.
Features
<ol>
<li>Control voting feature via voting on/off (admin feature)</li>
<li>Control allow or disallow post author to vote his own posts (admin feature)</li>
<li>Control allow or disallow public voting (admin feature)</li>
<li>Customise vote and voted text (admin feature)</li>
<li>Customise vote and voted buttons images (admin feature)</li>
<li>Customise alert message for non logged in users (admin feature)</li>
<li>Voting logs for site administrator (admin feature)</li>
<li>Sort voting logs by vote count or voted date (admin feature)</li>
<li>Show current vote count and vote button on frontend templates</li>
<li>Compitible with almost all of the themes. You just need to call required function from your template</li>
<li>Total vote count widget</li>
<li>Top voted widget</li>
<li>Now public voting supported.</li>
<li>Now shortcode supported. e.g. [wpvoting]</li>
<li>Top voted posts list shortcode</li>
</ol>
Features in future releases
<ol>
<li>Export to CSV for admin voting logs</li>
<li>Registered user voting logs</li>
<li>Re-implement backend voting log list with WP_List_Table class</li>
</ol>
Note-1: Kindly please rate this plugin or vote the compatibility. So I could review it and improve the quality of this plugin. Appreciate your help!
Resources
http://www.garyc40.com/2010/03/5-tips-for-using-ajax-in-wordpress/
http://www.onextrapixel.com/2009/06/22/how-to-add-pagination-into-list-of-records-or-wordpress-plugin/
http://www.onextrapixel.com/2009/07/01/how-to-design-and-style-your-wordpress-plugin-admin-panel/
http://planetozh.com/blog/2009/09/top-10-most-common-coding-mistakes-in-wordpress-plugins/
https://wordpress.org/extend/plugins/vote-it-up/
https://wordpress.org/extend/plugins/shortcodes-ultimate/

WP Voting

Site owner to add voting functionality to the blog posts.

SweepWidget

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WP Voting vs SweepWidget – Contests, Giveaways, Sweepstakes & Photo Contests