In Swift you can not have more than one active text-enabled question at a time, because each account is assigned only one phone number for response collection. When you activate a text-enabled question, it takes over the phone number to ensure that all the incoming responses are counted for the desired poll only.
That is not the case for web polls. All of the web enabled polls you create are always active. Every web-enabled poll has a unique URL, which you can find in the question's detailed view. Just click "Web voting" and you will be taken to the poll's unique URL.