TRENTON -- The state Legislature on Thursday will begin to consider bills that would raise taxes on gasoline by 23 cents a gallon while reducing or eliminating taxes on estates and some income, a deal that has support and opposition cross party lines.

Lawmakers in both the Senate and Assembly introduced the legislation Monday, seeking to tack a 12.5 percent tax onto the state's 14.5 cent motor fuels and petroleum tax in order to spend $20 billion over the next 10 years on infrastructure improvements.

The Transportation Trust Fund expires at the end of the month and as running out of money for new projects.

Here are 9 things you need to know about New Jersey's historically low gas tax:

1. The first New Jersey gas tax was 2 cents a gallon, and took effect in 1927.

2. The last time the gas tax was increased was 1988. The 28-year gap since that last increase is the longest in state history.

3. The 14.5 cent gas tax is now 49th in the U.S., with only Alaska being lower. If the 12.5 percent increase is enacted, New Jersey would have the seventh-highest gas tax. But because the tax depends on the price of gasoline, the Garden State could move up or down on that list.

4. The 14.5 cent gas tax is made up of a 10.5-cent per gallon tax on motor fuels and a 4 cent Petroleum Products Gross Receipts Tax. Most of the revenue from those taxes is already dedicated to the trust fund, but voters will be asked this fall to constitutionally dedicate all existing and future gas tax revenue.

5. Gov. Tom Kean set up the Transportation Trust Fund as self-sustaining by limiting how much governors could borrow to allow debt to be paid off so it could be perpetually replenished. Governor after governor sabotaged that by increasing the borrowing and not increasing the source of money going into the fund. Right now, all that's left is debt.

6. Gov. Christie Whitman once proposed raising the gas tax -- with some of the proceeds to pay for open space preservation.

7. According to a state senator, New Jersey has nearly 7 million licensed drivers who would get hit with an increase. Officials have said anywhere from 20 to 40 percent of the gas tax is paid by out-of-state motorists.

8. Gov. Chris Christie's opponents charge that his controversial decision to cancel a rail tunnel under the Hudson River to New York early in his term was motivated by a desire to grab funds to pay for New Jersey road projects and avoid raising the gas tax.

9. The gas tax is projected to generate about $750 million this year, and a 23-cent increase would add another $1.4 billion a year. Jersey motorists living near state borders would have a little relief. Gas would still cost more in New York and Pennsylvania, but would be cheaper in Delaware.

Samantha Marcus may be reached at smarcus@njadvancemedia.com. Follow her on Twitter @samanthamarcus. Find NJ.com Politics on Facebook.