Dane County leaders said they're committed to letting voters decide whether to adopt a half-cent sales tax for regional transportation improvements - even though Gov. Jim Doyle vetoed a binding referendum on the tax.

But the state senator who pushed for the referendum in the 2009-11 state budget, which Doyle signed Monday, said the veto could limit how much say voters in smaller communities have in the imposition and use of the tax by a county Regional Transit Authority.

State Sen. Jon Erpenbach, D-Waunakee, also said the binding referendum provision was critical to the RTA being included in the state budget.

"Without the referendum in this I wouldn't have supported the RTA language and it wouldn't have been in the budget," Erpenbach said. "I was real surprised (about the veto), number one, and number two, pretty mad about it. It's something everyone agreed to."

Doyle said in a veto message, "I object to state mandated referenda deciding questions on local transit."

Doyle also vetoed language lawmakers agreed to that would have allowed Dane County to spend up to 25 percent of any sales tax generated by the RTA on roads.