.htaccess redirecting errors - .htaccess

Question

First off I am using the Codeigniter Framework so this issue is a workaround the way CI process URLs along with the current redirects I have set up using mod_rewrite.
I am trying to get a URL like this /?gclid=somestringgoeshere to redirect to /index.php?/home/gclid/somestringgoeshere.
The current .htaccess I have set is below
<IfModule mod_rewrite.c>
Options +FollowSymlinks
RewriteEngine On
RewriteCond %{REQUEST_URI} ^system.*
RewriteRule ^(.*)$ /index.php?/$1 [L]
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule ^([^_]+)-([^_]+)-([^_]+)-([^_]+)-([^_]+)-([^_]+)-([^.]+)$ index.php?/$1_$2_$3_$4_$5_$6_$7 [L]
RewriteRule ^([^_]+)-([^_]+)-([^_]+)-([^_]+)-([^_]+)-([^.]+)$ index.php?/$1_$2_$3_$4_$5_$6 [L]
RewriteRule ^([^_]+)-([^_]+)-([^_]+)-([^_]+)-([^.]+)$ index.php?/$1_$2_$3_$4_$5 [L]
RewriteRule ^([^_]+)-([^_]+)-([^_]+)-([^.]+)$ index.php?/$1_$2_$3_$4 [L]
RewriteRule ^([^_]+)-([^_]+)-([^.]+)$ index.php?/$1_$2_$3 [L]
RewriteRule ^([^_]+)-([^.]+)$ index.php?/$1_$2 [L]
# Checks to see if the user is attempting to access a valid file,
# such as an image or css document, if this isn't true it sends the
# request to index.php
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
# This last condition enables access to the images and css folders, and the robots.txt file
# Submitted by Michael Radlmaier (mradlmaier)
RewriteCond $1 !^(index\.php|images|robots\.txt|css)
RewriteRule ^(.*)$ index.php?/$1 [L]
</IfModule>
I am trying to use the following code right above the first set up rewrite conditions and rule's to catch it before it try's anything else
RewriteRule ^?gclid=(.*)$ index.php?/home/gclid/$1 [L]
and
RewriteRule ^\?gclid=(.*)$ index.php?/home/gclid/$1 [L]
and
RewriteRule ^/?gclid=(.*)$ index.php?/home/gclid/$1 [L]
All either don't show the correct page or come up with a 500 internal error.

Answer 1

The URI’s query can only be tested with the RewriteCond directive:
RewriteCond %{QUERY_STRING} ^gclid=(.*)
RewriteRule ^$ index.php?/home/gclid/%1 [L]
Or more general (will consider further query parameters):
RewriteCond %{QUERY_STRING} ^([^&]*&)*gclid=([^&]*)
RewriteRule ^$ index.php?/home/gclid/%2 [L]
Oh, by the way: RewriteCond directives only correspond to the first following RewriteRule directive.