(CNN)On the Saturday before Utah's primary, Salt Lake County Mayor Ben McAdams was hustling — knocking on doors and on the hunt for persuadable Republicans to support his congressional bid.
The real race to watch in Utah this November is not Mitt Romney's -- it's Mia Love's
Here in Utah's Fourth District, a boot-shaped district covering the suburbs south of Salt Lake City, the primary election Tuesday was a foregone conclusion. The highly competitive race between this popular Democratic mayor and his opponent, Republican Rep. Mia Love, was set this spring when they each secured their party's nomination. Still, recognizing the steep climb he faces to unseat Love, McAdams dashed from house to house, showing the earnest energy and persistence of a former Mormon missionary.
Laced up in a pair of blue Asics that serve as his "parade shoes," McAdams scanned the driveways to game out which voters were home, sometimes hitting doors that weren't on his list. While walking, he scribbled notes on his campaign literature for voters who were out: "Sorry I missed you," he wrote next to his name, tucking it under their doormat.
While much of the attention in Utah has been focused on the reemergence of Mitt Romney, who is running for US Senate, the Love-McAdams race is much more consequential to both parties.
As Republicans try to maintain control of the House, there are few GOP districts in the country where President Donald Trump could cast as long a shadow as he will here. In 2016, Trump drew just 39% of the vote in Utah's 4th District, to Clinton's 32%, with independent candidate Evan McMullin sweeping up much of the remainder.
The race between these two charismatic players will be one of the most fascinating midterm contests this fall, not only because Love has been one of the most high-profile Republicans to stand up to Trump on immigration, but because national Democrats see McAdams as one of their best chances to gain a foothold on red turf.
Salt Lake County covers 85% of the 4th District, giving McAdams a distinct advantage when it comes to local issues. When an undecided Republican City Councilman passes by, the Mayor notes that he is staying on top of much-needed street repairs on a nearby corridor. When a mother leaned out the car window to offer encouragement—"We love you. We'll do anything we can to help," 38-year-old Candice Jorgensen told him — McAdams leaned in to give her son a tip for scout camp: "Try the mulberry juice."
Though McAdams will be well-funded with strong backing from Democrats nationally, he acknowledges the difficulty of his quest in a state where Republicans outnumber Democrats by more than four to one. Strategists on both sides estimate that McAdams must win a fifth to a quarter of Republican votes to prevail.
Love's challenge will be to turn out Republicans who are not enamored with the President, particularly in more conservative Utah County. Trump's opportunity to nominate a conservative justice to the Supreme Court could help energize the base in Love's district, and she is also likely to get a lift from Romney, the former Republican presidential nominee who is at the top of the ballot as he runs for Utah's open U.S. Senate seat.
But Trump's crude broadsides and harsh immigration policies have been an affront to Utah's huge population of Mormons, who embrace a doctrine of acceptance and inclusivity toward immigrants.
In such a staunchly Republican state, one would expect a Republican president to have "a substantially higher" approval rating than Trump does, said Brigham Young University Political Science Professor Chris Karpowitz.
Karpowitz notes that while Trump is popular among GOP voters nationally, his approval rating is unusually low among Republicans in Utah.
"He is, in so many ways, the polar opposite of what conservative Mormons are taught to stand up for," Karpowitz said.
The separation of families at the border was particularly abhorrent to Utah Mormons, because the importance of keeping families together is at the core of the doctrine of the Mormon Church. The neighborhood where McAdams knocked on doors this past weekend was dotted with signs supporting immigrants; some placards in the windows opposed the separation of families.
Many Mormon missionaries, Karpowitz added, have served "in places like Mexico, Guatemala, El Salvador, Honduras and Nicaragua. They have a sense of what life is like on the ground in those countries — and why refugees might be trying to get in to the United States."
Love was among the first Republicans to strongly condemn family separations at the border, calling the policy "absolutely terrible." The Mormon Church also rebuked the Trump administration's "zero-tolerance" policy and "aggressive and insensitive treatment of these families."
The Utah congresswoman argues that she has been an independent voice for Utah, particularly on immigration issues. As the daughter of immigrants from Haiti, she gained national attention when Trump demeaned Haiti and several African nations as "shithole countries."
When asked how she has tried to influence Trump on immigration, Love said bluntly in a telephone interview that she doesn't expect leadership from the President on the issue.
"We cannot depend on the White House to make all these decisions for us," she said. "At one point he said that there was nothing he was going to do about what was happening at the border. The next moment he signs an executive order to stop what's happening at the border. One minute he comes in and says, 'You have to vote on immigration,' the next minute he tweets 'I don't know why you're wasting your time on immigration.'"
"It's completely unpredictable, which is why I keep pushing Paul Ryan and Kevin McCarthy to take the reins and do what they are supposed to do, which is to enact law," Love said.
While Love is creating that distance between herself and the President, McAdams argues that her votes have aligned with the President's position 96% of the time, according to an analysis by FiveThirtyEight.
"The movement to the center that we've seen from her in the last couple of months is nothing more than just show for an election," McAdams said, as he walked through the streets of Millcreek on Saturday. "I don't know how much we should be applauding her recent move to the center in light of her past record and her past statements. How much of this is a real change of heart, and how much is for show?"
Love, who spent last weekend in Washington trying to revive immigration legislation that later failed, chafed at that characterization.
"We have been out front, on our own, many times on immigration, even before he got in the race," Love said. "It's actually incredibly offensive that he would think that I would need to see his face to remind myself that I am a daughter of immigrants. It's absolutely arrogant."
She added that it took "a lot of courage" to buck her party's leadership and sign the discharge petition that has forced the immigration debate on the House floor.
"We were the only ones in the delegation that did it. No one else did," she said. "And I guarantee you, we would not have had a vote last week, and we would not be having a vote this week, if it were not for that discharge petition."
After the immigration compromise bill failed this week, the McAdams campaign criticized Love for not doing more to force immigration legislation through Congress.
"People's lives are in limbo, families are being torn apart, our economy is suffering, and Rep. Love has completely failed to deliver," McAdams' campaign manager Andrew Roberts said.