Yes, the official Twitter plugin for WordPress includes this functionality in its Twitter Card markup.
Store a Twitter handle for the site. Example: verge
Output the site handle as a twitter:site meta element value to be picked up by Twitter Cards, prepending “@”.
<meta name="twitter:site" content="@verge">
Store a Twitter handle for each WordPress profile. Example: WordPress user 1 is jack
Output the author handle as a twitter:creator meta element value to be picked up by Twitter Cards, prepending “@”.
<meta name="twitter:creator" content="@jack">
Only one Twitter handle is allowed for each field. Choose just one handle in a co-author situation.