How to add Google events tracking code to CTA button on popup?

I have installed a pop-up plugin on my Wordpress site. The pop-up has a CTA button that links to an inner page and I would like to track clicks on the button using Google events tracking.

This is the Google analytics code I'm using:

onClick="ga('send', 'event', { eventCategory: 'popup', eventAction: 'click'});"

Code (markup):

...and the following code is from the plugin which outputs the CTA button link:

if ( $has_cta ) {
        $cta_button_tag = sprintf(
            '<a href="%1$s" class="wdpu-cta" target="%2$s">%3$s</a>',
            esc_url( $this->cta_link ),
            esc_attr( $cta_target ),
            esc_html( $this->cta_label )
        );

Code (markup):

I already tried adding the code directly to the anchor tag but am getting an error when loading the site admin page:

Parse error: syntax error, unexpected T_STRING in...

Code (markup):

Also I was wondering do I need to add anything to the Google analytics code in my site's header file to get the tracking code to work?