倒计时Jquery更新DB

I'm doing a vote system to a website i'm making where i need to make a count down but it need to have some functionability, i'm not realy good with jquery.

So this is my database:

Table: Votes

Rows: min_users, active

Let's say that i want a minimum of 100 users to vote in this poll, when it reaches 100 users it will start a countdown of lets say 7 days, when the countdown ends it will update the database and set active to 0.

I've seen some Jquery examples of updating a database, but i'm not realy sure whats the currect way to do what i want it to work.

I'm also making this with Laravel 5.