As Rep. Steve Knight and challenger Katie Hill raise millions in a race that could help determine whether the House stays in Republican control or turns blue, each is seeking an edge.

What remains unclear is whether that advantage will come through a Republican bump from the White House, a visit by former President Barack Obama to a far-reaching district in northern Los Angeles County or from a wild card.

The race for California’s 25th Congressional District seat, circled nationally by both parties, involves candidates who couldn’t be more different.

Knight, 51, is a two-term Republican incumbent with a military and law enforcement background and a famous father – record-setting test pilot Pete Knight, who as a California state senator authored the now-nullified ban on same-sex marriage.

Hill, 31, has lived in the district since childhood and, in her first run for office, has balanced a grassroots ground force of more than 1,000 volunteers with appearances on documentary segments of HBO’s “VICE News Tonight.” She has gained attention for a campaign that raised nearly $2.5 million through June and for identifying as bisexual.

Knight raised about $1.7 million but still had about $1.3 million cash on hand through June, far more than Hill, according to the Federal Election Commission. Hill suggested the incumbent has a money edge partly because of fundraising for Knight and other campaigns by leaders, including President Donald Trump.

“The president has given a lot of money to a lot of candidates,” Knight said, noting that he couldn’t confirm the Trump connection but it was likely true.

“Just like (House Minority Leader) Nancy Pelosi has given to our opponent, I’m sure our leadership has given a lot to our members,” he said.

The contest is being called a toss-up by The Cook Political Report and Sabato’s Crystal Ball, both high-profile political prognosticators. An analysis by Politico suggests Hill is in the lead.

“I believe it’s all going to boil down to the national mood and the turnout,” said Tim Allison, a political scientist at CSU Channel Islands.

A day after calling out Trump by name, Obama campaigned for Hill and a half-dozen other California Democrats in so-called swing districts at an Orange County rally. Hill was the only one of the seven candidates who didn’t attend the rally.

It was an absence her opponent noticed.

“She didn’t go,” Knight said, responding to a question about whether the Obama endorsement would bring Hill voters. “So, I don’t know if it helped her at all.”

Instead, Hill was meeting with hundreds of union members at a Los Angeles County Federation of Labor barbecue she had committed to months earlier.

“I can’t blow something like that off,” she said, expressing her respect for Obama and saying his endorsement is a sign of momentum. She downplayed its role in attracting new voters.

“I think a bigger bump would come if he actually came to the district,” Hill said, adding that she plans to ask Obama to make such an appearance.

Retired California Lutheran University political scientist Herb Gooch said Obama’s involvement could be used to stir up voters in both parties.

“Historically, the Republicans have sort of used Obama as the nightmare ... sort of ‘the enemy is at foot,’” said Gooch. “Right now, I think the Democrats are using Trump to more effect in that role.”

The current president has tweeted repeatedly about the importance of the midterm elections in keeping a Republican majority in the House. Any involvement in the Knight-Hill race could be complicated by a 2016 election in which the 25th District voted for Hillary Clinton over Trump by a 50 percent to 44 percent margin.

If Trump decides to stump for Knight and other GOP congressmen in California, where Clinton won overwhelmingly, it could backfire, Allison said.

“What Steve Knight needs to do is localize the election. If this is an election about the national support for the president, then Steve Knight has a difficult road,” said Allison.

“The last thing an endangered Republican in California would want is a visit from the president,” he said.

This week, Knight said he has neither asked for nor been offered Trump’s endorsement.

“We kind of run our own ship. We’re not really reaching out to a lot of people,” he said, later noting that an invitation has been sent to Vice President Mike Pence to visit the district, but it wasn’t clear whether that would happen.

Or, the election could come down to voter turnout. And a Trump appearance in California could galvanize the president’s supporters and push fundraising efforts for Republicans.

“I think there’s a definite possibility,” Hill said of a Trump visit. “I would be surprised if he doesn’t.”