Legislation allowing tax breaks on savings for school expenses, including private school tuition, failed again to advance in the Senate as Democrats blocked consideration of the measure.

The 58-42 vote Thursday was the fourth successful effort by Democrats since last fall to block consideration of the bill. The measure is a key part of the Republican agenda on education, a pivotal issue in mid-term congressional elections this year.Three Democrats sided with the Republican majority, but 60 votes were needed to force consideration.

Majority Leader Trent Lott of Mississippi scheduled another vote for Monday.

The bill would expand tax-favored savings accounts created last year to help families save for college. The maximum yearly contribution would be raised from $500 to $2000.