Kristen Wyatt, AP 

Coloradans trying to suss out the best candidate in this year's Senate contest may need an accounting degree.

The race between Democratic Sen. Michael Bennet and Republican Ken Buck  has already turned into a nitpicky debate over federal spending. 

A day after an ad accusing Bennet of joining a "spending spree" started airing in Denver and Colorado Springs, Bennet's camp had a 27-page response arguing the government spending was mostly to fund wars in Iraq and Afghanistan.

Buck insists the war funding is just one piece of the deficit. It's an argument Colorado voters are likely to see rehashed over and over through November, as voters say the economy is their top concern.

The ad comes from a conservative advocacy group affiliated with former Republican White House aides Karl Rove and Ed Gillespie. The group spent $425,000 on an ad airing in Denver and Colorado Springs arguing Bennet signed off on "billions in government pork" and joined two votes to raise the federal debt ceiling.

Bennet argued that the debt votes were necessary to keep government functioning. Bennet also pointed out that one of the votes described in the bill a $106 billion measure in June 2009 was largely a measure to pay for the wars.

Bennet's spokesman, Trevor Kincaid, defended the senator's spending votes Wednesday and called the conservative ad misleading. He said the ad is "attacking Michael for providing our troops with the resources they need to complete their mission."

A spokesman for the group that funded the ad, Crossroads GPS, said Bennet should expect more of the same attacks through Election Day.

"Colorado is one of our key races, and Michael Bennet has shown no responsibility on fiscal issues," said Jonathan Collegio, a spokesman for the Washington-based Crossroads GPS, which does not have to disclose its donors.

Buck's spokesman, Owen Loftus, said the spending criticism against Bennet is fair. Loftus pointed out Bennet's vote for last year's Cash for Clunkers program to stimulate automobile sales.

"This is a lot more than just funding the troops," Loftus said. "This is a much bigger issue that Bennet has not answered, his addiction to spending."

Read the full article in the Greeley Tribune.