Story highlights Many Republican senators haven't endorsed Trump

A spokeswoman for the NRSC downplayed the importance of the message

(CNN) The official committee tasked with electing Republicans to the Senate wants you to endorse Donald Trump for president -- even though several of its own members refuse to do so.

Like much of the Republican establishment's relationship with Trump, it's a little awkward: The National Republican Senatorial Committee sent out a fundraising email to supporters Friday urging them to sign up to endorse the presumptive GOP nominee.

"You have the opportunity to endorse Donald J. Trump for president -- even before convention makes it official," the message, one of many messages groups such as the NRSC send supporters to build their email lists and raise money, reads. "Don't miss out to be among Mr. Trump's first endorsers! Add your name to confirm Mr. Trump can count on your vote in November."

However, many of the group's own members in the Senate haven't taken that step.

Mark Kirk of Illinois, Lindsey Graham of South Carolina and Ben Sasse of Nebraska have outright refused to endorse Trump. Other members, including Cory Gardner of Colorado and Ted Cruz of Texas, have been non-committal about whether they will support him, let alone formally endorse him.

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