The conservative group Americans for Prosperity made their backing of Republican U.S. Sen. Cory Gardner evident Wednesday afternoon with an event in Centennial.

AFP’s national president, veteran strategist Tim Phillips, came to Colorado for the event, according to a spokesman. Wednesday night’s event was also put on my AFP Action, the organization’s super PAC.

Americans for Prosperity was started by Charles and David Koch, the billionaire brothers who support conservative, usually pro-business causes. AFP said David is no longer active with the political operation. 

“As we looked over his time it the Senate, he’s someone who has shown leadership and principled positions on trade and criminal justice and he’s been a champion on those issues,” said Jesse Mallory, AFP’s Colorado director and a senior advisor to AFP Action. 

The organization, however, said it’s eschewing partisan labels and in the future might support like-minded Democrats.

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Nonetheless, the Koch label attracted heat from Democratic operatives Wednesday. The state Democratic Party sent an email to reporters Wednesday noting the similarity in positions between Gardner and Americans for Prosperity.

The press release said Coloradans reject the “Kochs’ corporate special interest agenda.”

“Despite frequent fundraisers with D.C. lobbyists, Gardner still hasn’t held a reelection kickoff in Colorado, and there is no sign of a rally or other public event today,” the state party alleged.

Gardner was in Washington on Wednesday, his office confirmed.

He introduced a bill with Sen. Tim Kaine, D-Virginia, to augment veterans’ ownership of small businesses, including training.

“This bill will make sure our nation’s veterans who wish to start a business are introduced to the skills, knowledge, and resources they need to live their dream and establish a successful business,” Gardner said in a statement.