(Bloomberg) -- A super political action committee with close ties to billionaire donor Charles Koch has spent $4 million on Republican presidential hopeful Nikki Haley, with more spending planned in the coming weeks.

The money has gone to canvassing in early voting states and advertising in Iowa, New Hampshire, South Carolina, Arkansas, Tennessee, North Carolina, and Virginia, according to Americans for Prosperity Action spokesman Bill Riggs. The Koch-backed political group said in late November it would help Haley in her bid to defeat frontrunner Donald Trump for the Republican nomination.

The group hasn’t said how much in total it could spend on efforts to boost Haley, and Riggs didn’t provide a figure for future expenditures. So far, the amount comes close to matching the $5.7 million her campaign has spent on advertising, according to AdImpact, which tracks political ad spending.

The resources come at a critical time for Haley, who has kept a lean campaign in Iowa, the first contest in the Republican nomination process. The surge of money from Americans for Prosperity, plus endorsements from other notable business figures including JPMorgan Chase & Co. Jamie Dimon, have given her campaign new momentum weeks ahead of the Jan. 15 Iowa caucuses.

Earlier: Nikki Haley Backed by Charles Koch-Tied PAC in Bid to Beat Trump

The former United Nations Ambassador has increased her standing in the polls in recent months, but still trails Trump by roughly 30 percentage points in the early voting states. Florida Governor Ron DeSantis, her closest rival in the polls, has concentrated his efforts in Iowa, and has little presence in states that vote later.

Waning support for DeSantis, who was once seen as the main Trump alternative, and Trump’s strong lead has prompted prominent political donors to give Haley a second look. Citadel’s Ken Griffin, a major GOP donor, has said he’s considering contributing to her, and billionaire investor Bill Ackman, who has traditionally given to Democrats, said he’s interested in her candidacy.

Americans for Prosperity Action is also building its volunteer base to do voter outreach. In recent weeks, they have contacted 180,000 voters on Haley’s behalf, Riggs said.

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