Often, feedback or votes on Web pages are sent back via POST requests. You can send this kind of information via PowerShell as well. You should simply create a POST request with the target URL and the desired parameters/information and send it off:
$url = "http://someurl"
$parameters = "vote=true&poll_id=2" # your POST parameters
$parameters = "vote=true&poll_id=2" # your POST parameters
$http_request = New-Object -ComObject Msxml2.XMLHTTP
$http_request.open('POST', $url, $false)
$http_request.setRequestHeader("Content-type",
"application/x-www-form-urlencoded")
$http_request.setRequestHeader("Content-length", $parameters.length)
$http_request.setRequestHeader("Connection", "close")
$http_request.send($parameters)
$http_request.statusText