In his first-ever congressional endorsement since running for president, presumptive Republican presidential nominee Donald Trump endorsed Rep. Renee Ellmers (R) of North Carolina.

"Renee was the first congresswoman to endorse me, and she really was terrific and boy is she a fighter," Trump said in a robocall Sunday. "I need her help in Washington so we can work together to defeat ISIS, secure our border, and bring back jobs and frankly, so many other things. Renee knows how to do it. She gets it, and together we will make America great again."

The Ellmers-Trump partnership makes some sense – both are waging a war against the Republican establishment.

Elected as a tea party candidate six years ago, Ms. Ellmers now faces serious opposition from conservative groups and politicians who once endorsed her candidacy. Because like Mr. Trump, Representative Ellmers has been criticized by those who fear she sits far too left on typically conservative cornerstones such as government spending and abortion. Since being elected as a strict conservative, Ellmers worked closely with former House Speaker John Boehner and voted for a budget deal to raise spending caps as well as helped kill the "Pain-Capable Unborn Child Protection Act" which would create a 20-week abortion ban.

In a tight race, Trump's endorsement might help.

"I am proud to be the first member of Congress to have received an endorsement from the Republican nominee and soon-to-be-president Donald Trump," Ellmers said in a statement to Fox News Sunday.

Thank you @realDonaldTrump for the endorsement. TOGETHER WE ARE GOING TO MAKE AMERICA GREAT AGAIN. pic.twitter.com/4LcraZDKaN — Renee Ellmers (@Renee4Congress) June 4, 2016

Trump narrowly won the North Carolina primary on March 15 with 40.2 percent of the vote and 29 delegates, while Texas Sen. Ted Cruz came in second with 36.8 percent of the vote and 27 delegates. Ohio Gov. John Kasich and Florida Sen. Marco Rubio trailed in third and fourth place with 12.7 percent and 7.7 percent of the public vote, respectively.

Ellmers has held North Carolina's 2nd congressional district, located in the center of the state, since 2010. But on June 7, Ellmers faces Dr. Greg Brannon, who has previously run two failed campaigns for North Carolina Senator, and fellow House incumbent Rep. George Holding. Mr. Holding previously represented District 13 but due to redistricting in the state Holding and Ellmers are now campaigning for the same constituents.

"Last month, a federal three-judge panel found that Republicans drew two of the state's congressional districts illegally, packing more black voters into districts where they already had a plurality, thus boosting Republican odds by 'bleaching' surrounding districts," Patrik Jonsson wrote for The Christian Science Monitor in March. "The result is, pretty much everyone agrees, a mess. The congressional candidates are still on the ballot along with the presidential and local candidates. But all the congressional votes will not be counted, and a new congressional primary with the new districts is scheduled for June 7."

Political outsiders, such as Trump and Democratic presidential candidate Bernie Sanders, have voiced their opposition to redistricting and the "rigged" repercussions of gerrymandering.

Get the Monitor Stories you care about delivered to your inbox. By signing up, you agree to our Privacy Policy

Not only is Ellmers facing a fellow incumbent to hold onto her congressional position, but she also faces opposition from the organizations Club for Growth and Americans for Prosperity (AFP), funded by the Koch brothers who have also voiced opposition to Donald Trump's presidential campaign. AFP has not endorsed one of Ellmers' opponents, but this is the first time the group has rallied against a GOP incumbent in a primary. The Susan B. Anthony List, a pro-life organization, endorsed Holding over Ellmers, marking the first time the group has endorsed a male candidate over a pro-life, female candidate.

"Because of the intra-party face-off, at least one incumbent will become the first GOP casualty this year," writes NPR's Jessica Taylor Monday. "But will the more pragmatic approach Ellmers brags about triumph – or will conservative groups propel one of her rivals to win, claiming victory for conservative orthodoxy?"