The GOP is desperately trying to maintain control of the Colorado Senate.

Two key Republicans locked in tight state Senate races in Colorado are hoping outside money from the Koch brothers can fend off surging Democrats this year.

The Koch’s Americans for Prosperity political action committee has committed to help elect Tim Neville and Christine Jensen in their Senate campaigns.

This is the first time the Koch’s powerhouse money machine, bankrolled by David and Charles Koch, the Wichita-based billionaire businessmen, has been directly involved in local Colorado campaigns, the Colorado Springs Gazette reports.

The Koch’s network previously announced it planned to spend as much as $400 million nationally boosting Republicans during the 2018 election cycle.

The group backs Republicans who aggressively work towards slashing taxes on wealthy individuals, as well as corporations.

It’s not surprising that the far-right group has become active in the Colorado Senate race. Hoping to capitalize on the blue wave growing nationally this year, Democrats are trying to take back control of the Colorado House, where Republicans maintain a tenuous one-seat advantage.

A total of 17 out of the 35 seats in the Colorado Senate are contested in this election cycle.

Control of the Senate will likely come down to five toss-up races. And to date, the five Democratic women running in those five toss-up races are badly out-raising their Republican counterparts. All the more reason why the GOP needs Koch help.

Five of those key races include Koch beneficiaries, Neville and Jensen.

Neville represents Colorado Senate District 16, a moderate, suburban portion of the state southwest of Denver, which voted for Hillary Clinton over Trump by nine points in 2016, compared to four years earlier when President Barack Obama defeated Republican Mitt Romney by just two percentage points.

Despite the district’s moderating electorate, Neville remains a polarizing, far-right politician, who embraces a fierce anti-choice agenda.

In 2016, he “led a failed effort to cut off state funding of a teen pregnancy prevention program that reduced abortion and pregnancies each by more than 50 percent,” Rewire News reports.

Neville’s opponent is pro-choice Democrat Tammy Story, who has been endorsed by progressive groups such Planned Parenthood, as well as by Obama.

As for Republican Jensen, another Koch brothers beneficiary, she supports repealing Obamacare and has complained, “There are some that would much rather drive a nicer car than pay for the health care for their own family.”

In the battle for Senate District 20, Jensen is facing Democrat Jessie Danielson, who currently serves in the Colorado House. “This session, she worked on bills to advance equal pay for women, allow for local control of minimum-wage laws and create state tax deductions for military retirement benefits,” Westword notes.

Americans for Prosperity’s six-figure investment, which could balloon to seven figures, will go toward paying for TV ads and mailers in the state.

The cash infusion is also designed to boost Republican Walker Stapleton, who’s running for governor. Just this week though, one non-partisan campaign monitor shifted that race from “toss-up” to “lean Democrat,” in part because Colorado is seen trending Democratic this year.

Republicans in Colorado haven’t been able to win a governor’s race since 2002.