The influential political network funded by the billionaire Koch brothers will shift its focus from television advertising to grassroots organizing in the final month before Election Day, representatives for the groups told reporters Wednesday.

Notably, the network will now emphasize turning out dependable Republicans who are not enthusiastic about the presidential race, along with voters who are unsure about the presidential candidates but leaning toward supporting a Republican candidate for Senate. The strategy, targeting roughly 5 million voters overall, seeks to compensate for potentially anemic turnout amid low voter enthusiasm — recognizing that Republican nominee Donald Trump has not built out a ground operation as part of his campaign and is instead leaning on Republican National Committee resources.

“We’ve been more focused on the field efforts and what is needed there to have a strong impact, particularly given the gap in field operations and infrastructure that can really turn out voters,” said James Davis, executive vice president for strategic communications for Freedom Partners. “We have a robust field capability, and that’s something that distinguishes us from many others. So we have to play to that strength, particularly in the environment that we’re in in 2016.”

The groups under the Freedom Partners umbrella, including Americans for Prosperity, do not plan to reserve television time for advertising beyond Oct. 5, Davis said. They will also cancel roughly $500,000 in advertising for Sept. 28 through Oct. 4 in Florida, where recent polling has shown Republican Sen. Marco Rubio with a solid lead over his Democratic challenger, Rep. Patrick Murphy. Freedom Partners last month withdrew about $2 million in advertising in Ohio, where Republican Sen. Rob Portman has outpaced his Democratic rival, Ted Strickland.

Freedom Partners will now move their efforts to the ground in those states, in addition to Indiana, Missouri, Nevada, Pennsylvania and Wisconsin. The ground organization will double the network’s efforts from 2012, and mark the first time it has used grassroots volunteers to turn out voters, rather than to advocate for issues more broadly.

“We did express advocacy to defeat President Obama with our television” in 2012, said AFP President Tim Phillips, “but we never shifted our field efforts over to express advocacy.”

Of its roughly $250 million budget for the election, Freedom Partners said it would spend $42 million on TV and digital advertising, all told. The rest will now be focused on its ground game in addition to voter contact by phone and mail, and events.

The powerful network backed by Charles (pictured) and David Koch decided earlier this year that it would not commit any of its vast resources to support Trump’s bid for president, instead honing its energies on battleground Senate races.

But, even as Trump has recovered in recent polling, the groups have run up against political headwinds from the nominee’s historic unfavorable ratings. Rather than attempt to win over undecided voters under these circumstances, they have focused on motivating Republicans “disaffected by the top of the ticket or turned off by all the he-said/she-said stuff that’s going on.”

“Right now the enthusiasm among this segment is not where you want to see it for mid-September,” Phillips said. “So they’re becoming a key target for turnout for us. We’re not trying to persuade them: We know they’re going to be with us if they just turn out.”