WASHINGTON -- Loyalty to President Donald Trump has defined Republican primaries since 2016. So when he chooses sides in intraparty contests, it can make a difference.
It's not a perfect record. In the last month, Trump-backed GOP Reps. Scott Tipton of Colorado and Denver Riggleman of Virginia failed to get their party's nod for reelection. And North Carolina Republicans rejected Linda Bennett, Trump's choice for the seat formerly held by his chief of staff.
But the people who won those nominations all argued they were bigger Trump supporters, and Republican strategists say the president's endorsement still carries significant weight, especially in races with potentially lower turnout such as Tuesday's primary runoffs for two House districts in Texas and for Senate in Alabama. Trump has a personal connection to two of those races, making next week a key test of whether the value of his support has diminished.
His campaign does not think so.
"As we've seen in countless races this cycle, including the upcoming GOP runoffs in Alabama and Texas, an endorsement from President Trump brings unmatched enthusiasm for the candidates and this President's successful America First agenda," Trump campaign spokeswoman Samantha Zager said in a statement.
David McIntosh, president of the anti-tax Club for Growth, noted that in a recent Texas primary in which the club endorsed a challenger to longtime GOP Rep. Kay Granger, the group's polling found that some voters said they were backing the incumbent because of Trump's endorsement. Granger won handily.
"Republican voters were saying, 'Well, I need to be loyal to President Trump. I'll vote for the person he's endorsed,'" McIntosh said. "And I think that is the sentiment that's out there now."
The three recent losses aside, Trump-backed candidates have been overwhelmingly successful in their primaries this year. So far 82 candidates with a presidential endorsement have won their party's nomination, according to the Trump campaign. Many are also incumbents, who often have advantages in fundraising and name recognition.
One of the races where Trump has a more personal stake is in Texas' 13th District, where he endorsed Ronny Jackson, the former White House physician. Jackson was once Trump's nominee for Veterans Affairs secretary, but he withdrew from consideration amid allegations that he abused alcohol and mishandled prescription drugs. Jackson called the charges "completely false and fabricated."
Now, he's running in the open 13th District in the deep-red Texas Panhandle. Multiple Republicans said Trump's tweet supporting Jackson a few days before the March primary helped him advance to the runoff.