There are two tax increases included in the $34.1 billion Democrat-sponsored state budget approved Thursday and Gov. Chris Christie has repeatedly promised to veto both of them. One veteran New Jersey political expert said there is an upside and a downside for the governor if he follows through on his veto vow.

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"Obviously, the pro for a Republican governor is the claim that he vetoed taxes, that he's against tax hikes, that he has said that publicly and he's good for his word," said Peter Woolley, professor of political science at Fairleigh Dickinson University. "This has been a theme of many Republicans around the country, and it certainly has been a theme for Christie."

Many people believe Christie is still eyeing a run at the White House in 2016, and Woolley said vetoing tax hikes would only help him in a Republican primary.

There is some downside for the governor as well.

"The con, of course, is that his opponents want to tell the story that he vetoed a tax on the rich, and that Christie will forgo taxes on the rich and at the same time forgo delivering services to the poor," Woolley said.

Legislation to support spending in the budget would increase the income tax rate for those earning $1 million a year or more from 9.87 percent to 10.75. The tax hike would expire in three years. Another enabling bill would increase taxes on corporations for one year.

It is unclear when the governor will take action on the budget, but it does have to be signed and balanced by midnight June 30.