NASHVILLE (AP) - Opponents of a proposed constitutional amendment to ban an income tax in Tennessee say it's unnecessary and politically motivated.

The measure sponsored by Republican Rep. Glen Casada of Franklin was approved 73-17 on Thursday. The companion legislation passed the Senate last year, and Republican Senate Speaker Ron Ramsey of Blountville said he plans to bring it up at the beginning of the next General Assembly.

The proposal must now be approved by a two-thirds vote in each chamber of the next Legislature before it's placed on the ballot in 2014.

House Democratic Caucus Chairman Mike Turner of Nashville said the amendment is not necessary because an "income tax is clearly banned under the state constitution," and that the push for the measure is simply a "political ploy" by Republican leaders in particular.

"We do two things up here," Turner said after the vote. "We play politics, then after politics, we get arou nd to governing. The GOP majority hasn't gotten around to governing yet. They're still playing politics."

Casada acknowledged the constitution bans an income tax. But he noted about 11 years ago a state attorney general opined that the constitution does allow for such a tax, which led to a divisive, heated debate as to whether the state should implement one.

"So ... it's imperative that we make it very clear for future generations there is no taxing of earned income in Tennessee," he said.

However, lawmakers against the proposal said an income tax is another option for the state to raise revenue, even if it's a last resort.

"I think we should leave future governors free to make those proposals," said Rep. Mike Stewart, a Nashville Democrat.

Dick Williams, chairman of Tennesseans for Fair Taxation, agreed.

"Even if you're not in favor of an income tax at this time, we ... think this Legislature should not bind future Legislatures," he said.< /P>

Rep. Charles Curtiss said the state budget currently relies heavily on sales tax, but that more people are making purchases on the Internet and not paying sales tax, which could eventually affect that stream of revenue.

"We're going to have a reckoning day," said the Sparta Democrat.