Run gnome-terminal if it's not running

Question

I'm trying to write a script which will check if gnome-terminal is already open, switch to it if it is, or open it if it doesn't.

# check if terminal is running
EXISTS=$(pgrep gnome-terminal)

# if exists is a number
if [[ $EXISTS =~ ^[0-9]+$ ]]; then
    # switch to it
    wmctrl -a gnome-terminal
    echo "Switched to terminal"
else
    # else start it
    gnome-terminal
    echo "Started terminal"
fi

Nothing happens when I run this. It's difficult to test because the terminal is always open if I'm in there trying to do things.

Any ideas what I'm doing wrong? or is there a better way to go about this?