(CNN) Democratic Sen. Claire McCaskill's campaign is trying to persuade Missouri voters that she is not "one of those crazy Democrats," with a radio ad airing during the final stretch of her heated re-election fight.

The ad, which has been on air in mid-Missouri for roughly the past week, is part of McCaskill's closing argument in one of the country's most closely watched Senate races. As a Democrat in a state that backed President Donald Trump by double digits in 2016, McCaskill has touted her moderate credentials and urged voters to look at her accomplishments, not her party ID.

McCaskill's campaign appears to be doubling down on that message in the campaign's final days. In a new television ad released Tuesday by McCaskill's campaign, featuring veterans who support McCaskill, one man says of the incumbent senator, "you don't have to like her," before pushing back on Republican lines of attack and praising her work in the Senate.

The radio ad takes that message a step further, however, attempting to differentiate McCaskill from unnamed "crazy Democrats."

The ad features two middle-aged men discussing the Senate race between McCaskill and state Attorney General Josh Hawley, a Republican, whom the narrators describe as "a man in a hurry."

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