TALLAHASSEE (CBS4) — The Florida Senate rejected a slate of Democratic amendments to a massive elections bill Wednesday, setting up a potentially divisive debate over the measure in the waning days of the legislative session.

A few Republican-backed tweaks — including one intended to soften a rollback of the number of early voting days before an election — passed the chamber easily. But the Democratic amendments, many of which served as a way to drive home points about the main bill, were shot down, largely on voice votes.

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The final Senate vote on the measure (HB 1355), which will have to return to the House because of differences between the versions, is expected as soon as Thursday.

Democrats hammered away at the bill’s effects on college students, voter-registration organizations and the state’s presidential preference primary. Backed by progressive groups, the minority party has argued that the measure is aimed more at discouraging President Barack Obama’s base from returning to the polls in 2012 than at preventing fraud, as supporters insist.

The Senate did amend the bill to slightly back off the changes in early voting, which would have reduced the number of days for casting ballots before an election from 14 to six. The new amendment carves out eight days for early voting and would allow elections supervisors to keep polls open for up to 12 hours a day.

Supporters say the number of hours for early voting would remain the same in counties that went to 12-hour days, though Democrats only approved the measure begrudgingly.

“We’re still reducing the number of days that we’re having early voting,” said Sen. Oscar Braynon, D-Miami Gardens.

Democrats pushed back against new rules for voter-registration organizations, saying the measure could trip up scouting troupes and civic groups as easily as would-be election fraudsters.

“These are just little organizations,” Braynon said. “And what we’re doing is we’re putting [up] barriers.”

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But Sen. Miguel Diaz de la Portilla, the Miami Republican who sponsored the measure, downplayed the significance of the new rules and said they were only intended to make sure organizations turn in all the applications they get in a timely manner.

“It is really minimal regulation,” Diaz de la Portilla said.

Republicans also beat back a Democratic attempt to delay the state’s presidential preference primary, currently set for Jan. 31. The bill does include a measure that would have a committee by Oct. 1, 2011 set a new primary date, in an effort to defuse a showdown between legislative Republicans and the national party, which has threatened to strip the state of some of its delegates if the primary doesn’t comply with a calendar calling for it to be held no earlier than March.

Democrats — whose re-nomination of Obama is not in doubt but who are still stinging from a 2008 fight over the state’s delegates — called for the Senate to simply push the primary back and follow the rules.

“We’re giving up our authority to set a presidential primary in this state to a committee?” said Sen. Maria Sachs, D-Delray Beach. “I don’t think so. This is our obligation.”

But Diaz de la Portilla and other Republicans have argued that the measure would allow Florida to make sure its primary remains relevant, a distinction they say is necessary for the fourth largest state in the country and the largest swing state.

“I’m more worried about the voters of the state of Florida than I am about delegates,” he said.

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