U.S. Senate candidate Evan Bayh may have once received a paycheck from the U.S. Chamber of Commerce, but that hasn't stopped the business group from campaigning against the Democrat in the current election season, the New York Times reported Wednesday.

Bayh, a former U.S. senator, is seeking to reclaim his old seat in Indiana. He is in a close race with Republican Rep. Todd Young in an election that could determine which party controls the Senate come January. Bayh formerly was a paid adviser to the Chamber who made appearances and speeches criticizing excessive regulation, but now the business group is running ads against him.

The Chamber has leaned heavily Republican in its support of candidates in the past, but Democrats asked the business group to stay out of the race given Bayh's more conservative stance on business issues. Its decision to jump into the fray has angered the party.

"The fact that the U.S. Chamber has spent millions against Evan Bayh, a pro-business candidate who has even served on some of their advisory boards, rips away any pretense of bipartisanship," Sen. Chuck Schumer (D-N.Y.) told the newspaper.

The Chamber countered that Democrats are to blame by embracing policies the group cannot support and have given him a 55% grade on his voting record.

"If Mr. Schumer believes that a middle-of-the-road F is pro-business, he is wrong, and Hoosiers will have a fundamentally different view," Rob Engstrom, a senior vice president and the national political director for the chamber, told the Times.

A recent poll showed Bayh with a small lead over Young, but many political observers believe the race could be close. http://nyti.ms/2eabfV9

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