Nervous Tom Carper Tries to Influence GOP Primary Voters

Tom Carper apparently sent out a fundraising email attacking Rob Arlett, but why?

Senator Tom Carper is feeling some heat. He made the uncharacteristic move of acknowledging an opponent's existence by attacking them. Moreover, instead of his primary opponent, he attacked Rob Arlett who is not even the favorite to win the GOP nomination. That this is a fundraising email is a farce. Tom Carper doesn’t need the money so he is clearly trying to accomplish some other goals.