DENVER - U.S. Sen. Mark Udall's campaign will take the offensive Wednesday accusing congressman Cory Gardner of being in the pocket of a conservative group that two days earlier launched a nearly $1 million ad campaign targeting Udall.

Americans for Prosperity, a nonprofit based in Virginia, is paying $970,000 for three weeks of broadcast, cable and digital ads that highlight Udall's vote for the Affordable Care Act and the subsequent missteps the health care policy overhaul has suffered.

A significant portion of the media buy was in the Colorado Springs market.

Chris Harris, spokesman for Udall, said it's no surprise that a nonprofit funded largely by billionaire industrial tycoons Charles and David Koch is spending thousands to disparage Udall when the senator's toughest opponent this fall will be Gardner, a Republican from northern Colorado who has voted to increase access to domestic land for oil production.

"He has been a reliable vote for their radical agenda that would end Medicare as we know it, slash Social Security for our seniors and go back to the days when insurance companies could deny you coverage for a pre-existing condition," Harris said. "Coloradans want their leaders to fight for Colorado families, not radical special interests."

Harris said the campaign will release a detailed account of how Gardner has voted in line with AFP's recommendations Wednesday morning.

AFP gave Gardner a score of 83 percent approval for his votes on key issues identified by the nonprofit.

Udall scored zero.

Dustin Zvonek, head of AFP Colorado, said the ads released by Americans for Prosperity have nothing to do with Gardner.

"Our focus isn't the political race, as much as they want to make it about the political race," Zvonek said. "Our opponent is Obamacare; our focus is purely on the policy side."

Zvonek said Udall naturally would rather attack AFP as an organization than defend his stance on Obamacare.

As a 501(c)4 nonprofit, Americans for Prosperity is barred from endorsing candidates or working corroboratively with a campaign.

The nonprofits, also known as social welfare organizations, also are not required to disclose donors or expenditures in contrast with political action committees or campaigns that must disclose contributions to the Federal Election Commission.

Zvonek said they are proud of the support that Charles and David Koch have lent to AFP over the years.

The Koch brothers have also been generous donors to Gardner's campaigns beginning in 2011 with his primary race for Congressional District 4.

Koch Industries Inc. has donated $13,500 to Gardner's campaigns since 2011, according to Federal Election Commission records. The most recent donation of $1,000 came in December for Gardner's re-election campaign for the 4th Congressional District.

Last month, Gardner announced he would not seek re-election in the House but would instead challenge Udall for the Colorado Senate seat.

The announcement cleared the field as the three top Republican candidates in the race stepped aside to make way for Gardner's campaign.

The AFP ad campaign was launched three weeks after Gardner announced he would run for Senate.

Gardner's campaign responded to Udall's criticism Tuesday, saying that one of the reasons Gardner entered the race is to provide the public with an elected official who always tells the truth.

"Unfortunately, Sen. Udall's campaign has spent the last two weeks telling one lie after the next - part of a more disturbing pattern that must come to an end," said Alex Siciliano, spokesman for Gardner's campaign.

Gardner has an early deficit in financing, having $876,679 cash on hand at the last financial disclosure report to Udall's $4.7 million.

But outside money from conservative groups in this race might close the gap quickly.

Unseating Udall would be a step toward flipping the Senate to Republican control, something vital to conservative efforts to repeal or slow down the implementation of the Affordable Care Act.

There are 53 Democrats, 45 Republicans and two independents who align with Democrats in the Senate. The New York Times has identified 12 seats - including Udall's - that could flip political parties during November elections.

Harris said Gardner's votes in Congress frequently mirror the policy pushes from AFP and the Koch Industries PAC.

Harris points out that among other things, Gardner voted against a $60.4 billion federal relief aid package to assist recovery on the east coast from Hurricane Sandy.

AFP urged lawmakers to vote against the package because it spent money the government didn't have and was filled with unnecessary pork-spending.

Harris said that without the funding included in the Hurricane Sandy package, Colorado would not have received the funding it did for flood recovery. Some of the money Colorado received was included in the Sandy package for Community Development Block Grant Disaster Recovery Program.

The relief funding included the $710 million in Community Block Grants and transportation funding used to aid in Colorado's recovery from last year's Front Range floods.

But Gardner did help secure funding for flood recovery in Colorado, introducing a bill in the House that raised the cap on funds appropriated in the Disaster Relief Appropriations Act of 2013 and paving the way for more funds to flow into Colorado.

"Last fall, congressman Gardner worked in Sen. Udall's office to quickly find assistance for those impacted by the horrific flooding," Siciliano said. "While congressman Gardner has looked proudly at the relief their work has brought to the state, Sen. Udall seems to think it is a political weapon."


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