But the plan also carries with it the risk of failure and potentially builds political peril for his fellow Democrats who, unlike Patrick, will face voters in next year’s election.

The outcome of Patrick’s move is far from clear, though it has quieted chatter that the governor intended to endure a lame-duck status in his final two years before moving into the private sector.

In an interview, Patrick sloughed off suggestions that his push for a tax hike from 5.25 percent to 6.25 percent to fund transportation projects and education programs would create political chaos, or that his proposals were legacy driven.

He said his decision was fueled by what he sees as a unique chance to use the political influence he has gained to do something he believes is critical to the state’s future.

“As a relative newcomer to this line of work, I see people spending a lot time accumulating political capital but not much time spending it,’’ he said in an interview with the Globe. “For me, what is the point of having political capital if you can’t use it for the greater good?’’

Aides said Patrick’s decision to push for a sweeping plan in the twilight of his tenure should not come as a surprise, given that he has struck themes of raising tax revenue to pay for infrastructure projects and programs since his 2006 gubernatorial campaign.

“He’s talked ever since he got in that first race of making these kind of investments,’’ said Doug Rubin, his chief political adviser. He said Patrick waited until his final two years because of economic constraints and the prolonged recession.

Another aide, who did not want to speak publicly, said that during deliberations over the details of the plan, Patrick rejected advice that he scale back the size of the tax hikes in order to make it more politically acceptable.

The governor, the aide said, insisted they ignore potential political consequences and focus on putting forth a plan that fit his vision.

A nearly audible sigh of relief came from his office when legislative leaders did not declare his proposal “dead-on-arrival,” an oft-used term on Beacon Hill for governors’ sweeping budget plans, particularly those with big tax hikes.

Indeed, the way he packaged the tax plan could make it easier for key legislative blocs to accept. By lowering the sales tax to 4.5 percent from 6.25 percent, the plan will be attractive to the border communities, particularly in the Merrimack Valley, where there is stiff resistance to sales tax hikes as they compete with retailers in New Hampshire, which has no sales tax.

His plan would further restructure the income tax by doubling personal exemptions, a change that would benefit people at the lower end of the income scale, while putting a heavier burden on those at the top. That plays to Patrick’s long-standing desire to make the state income tax more progressive.

It also opens him up to a challenge from fiscal conservatives, who cite state Supreme Court rulings that prohibited the creation of a graduated tax.

But Paul Watanabe, the chairman of the political science department at the University Massachusetts Boston, said Patrick’s risk is reduced because the House and Senate are heavily dominated by the Democrats who will protect him from any political embarrassments.

“He is unburdened of having to face the electorate and relieved of any political accountability,’’ Watanabe said.

But Senate President Therese Murray was noncommittal about her support Wednesday. “He threw long, and maybe we’ll meet him somewhere down the road,” she said after the speech.

In the days after Patrick announced his decision to push a controversial and sweeping agenda, the proposal won plaudits — and drew some warnings — from those who have watched Beacon Hill for some time.

“Why shouldn’t he be bold?’’ said Michael S. Dukakis, the only previous governor in modern history who declared himself a lame duck two full years before the end of his term. “What is your legacy? Your legacy is doing everything you can do that you think is right and help build a better future for your state.”

Even a former Republican governor, Paul Cellucci, a strong antitax chief executive, said Patrick should use what influence he has left to pursue an aggressive agenda.