Since the November election, Mr. Rubio has joined a number of other GOP leaders, including Rep. Paul Ryan of Wisconsin and Majority Leader Eric Cantor of Virginia, who are working to soften the party's image and to realign its message in the eyes of voters.

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He then reposted the original message about his grandmother and the image of the text exchange.

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His last post, on February 12, linked to an Instagram image of himself with a young boy on prosthetic limbs with the message, "In the run up to the launch of my foundation in July I will give at least 10 kids mobility!"

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