Washington (CNN) Democratic Sen. Claire McCaskill, who is facing a tough reelection bid in her home state, admitted she used a private plane during parts of her RV tour of Missouri on Tuesday.

The admission came after a report in the conservative Washington Free Beacon, which reported that the movements of McCaskill's private jet had closely tracked with certain legs of her three-day RV tour to promote veterans' issues. Her campaign used a liveblog to track the tour and invited Missourians who saw the RV on the road to tweet with the hashtag "#bigblue."

McCaskill on Tuesday called the Free Beacon report "not accurate" and dismissed the notion that she was trying to hide the use of the plane.

"The plane picked me up at the end of one day after I spent all day on the RV and it took me to my overnight location," she told CNN. "And the next day we used the plane to add a stop. But I was on the RV totally -- two of the three days I was out."

She continued: "Anybody could have followed me ... they could have seen me when I got off the RV and when I got on the airplane ....there was no effort to hide anything."

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