The U.S. Chamber of Commerce is backing Republican Rep. Todd Young in the Indiana Senate race over former Sen. Evan Bayh, who worked for the chamber after leaving the Senate.

The chamber spent on Young’s behalf in his GOP primary against Rep. Marlin Stutzman, and now plans to spend at least $1 million in statewide ads beginning Monday, The Indianapolis Star reported. 

[GOP Senate PAC Spending $4 Million Against Bayh]

The chamber hired Bayh, a pro-business Democrat, in 2011 after he’d left the Senate, to push regulatory reform around the country. But Young has a better rating with the chamber than Bayh does, siding with the group 91 percent of the time in Congress compared to Bayh’s record of 55 percent during his previous Senate tenure.

Bayh’s late entry into the race shifted the contest in the Democrats’ favor. He has a financial advantage over Young, but outside groups like the Senate Leadership Fund are spending big against the former senator. 

The Rothenberg & Gonzales Political Report/Roll Call rates the race Tilts Democrat.