(CNN) Fresh off a staggering loss for Republicans in Pennsylvania's deep-red 18th district, President Donald Trump has a message to supporters: "I need allies."

And in a campaign email, Trump says he wants to know what qualities voters would like to see in congressional candidates in this year's midterm elections who would support his agenda -- even though the Republican Party controls both chambers of Congress.

"2018 is our chance to elect TRUMP ALLIES to the House and Senate who will give you the agenda you voted for," the email reads. "No more obstruction! We want what we voted for!

"But it cannot happen unless we put up GREAT candidates who stand by our values and prove to America that they have the fire to fight to Make America Great Again!"

The email from the Trump Make America Great Again Committee, a joint fundraising committee of the Trump 2020 campaign and the Republican National Committee, features a survey asking questions like whether a candidate "must hold populist views," "be able to appeal to hardworking Americans" or "be able to relate to his or her constituents."

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