AUGUSTA – Backers of a tribal racetrack casino in Washington County were unable to garner enough support Tuesday evening in the Maine Senate to fend off a veto from Gov. John Baldacci, who earlier had insisted on a two-thirds vote in each chamber to send the racino plan to referendum.

“[The governor] has been consistent and strong with the tribes that it needed two-thirds,” Baldacci spokesman Lee Umphrey said after the 22-13 Senate vote supporting the measure, two votes short of the two-thirds mark. “Because it didn’t reach that, he will veto it when it gets to his desk.”

The Senate vote came one day after the House gave its strong support to the measure, voting 97-40 – well over the two-thirds threshold – in favor of sending the matter to a November 2006 referendum.

The plan, if approved by voters, would allow the Passamaquoddy Tribe to open a new harness racing track with up to 1,500 slot machines near its reservations in Washington County.

Passamaquoddy Tribal Rep. Fred Moore said after the Senate vote that he had “no concerns whatsoever” about failing to reach the two-thirds mark, and pointed to the strong majorities the plan won in both bodies.

“The Legislature has been very clear that they want to send it out to voters,” said Moore, the bill’s sponsor. “This is the will of the people.”

The bill, LD 1690, must go before each house again before it reaches Baldacci’s desk. While there is a chance the Senate could increase its support in the final vote – likely today – most predict little movement in Tuesday’s tally.

Last week, Baldacci vetoed an almost identical bill, which lacked only the referendum component. In explaining his veto, he said he personally opposed gambling and argued that voters should have the say on any expansion of the industry in the state.

Current law allows as many as 1,500 slot machines in Bangor, where Penn National Gaming Inc. plans to open a temporary facility with 500 slots later this year near Bangor Raceway.

The Senate vote ran largely along geographic lines, with northern lawmakers in favor and southern lawmakers opposed.

The vote was preceded by a flurry of lobbying on the third floor of the State House, with tribal members and representatives of the anti-gambling group CasinosNO! stopping lawmakers in the hallways to make their cases.

In many respects, the Senate debate echoed that of the House. In general terms, supporters of the plan say it could bring much-needed jobs and revenue to Washington County, the state’s poorest.

“Let the voters decide on whether to bring economic development to Washington County after decades of economic destruction,” said Sen. Kevin Raye, R-Perry, in arguing for the referendum.

Opponents in the Senate on Tuesday said the slot machines would bring only social and economic ills, including bankruptcies, embezzlement and suicides.

“Fifteen hundred slot machines will take all the money out of Washington County and not even hiccup,” said Sen. Peter Mills, R-Skowhegan.

Opponents also have launched a repeal try of the existing state law allowing slots in Bangor, but have struggled in their effort to gather the 50,000-plus signatures needed to force a statewide referendum in 2006.