US News

Saving her Mass.

BOSTON — With the fate of his hard-fought health-care plan hanging in the balance, President Obama yesterday swooped into Boston in a desperate effort to save a historically Democratic Senate seat from falling to the GOP.

Obama took a break from last-minute negotiations on the health-care plan — which he has called his top domestic priority — to plead with Massachusetts voters to elect Martha Coakley, the state’s attorney general.

Coakley is in a surprisingly tight race against a previously little-known state legislator, Republican Scott Brown, to fill the late Ted Kennedy’s Senate seat.

The election is tomorrow.

“When the chips are down, when the tough votes come on the fights that matter to middle-class families around this commonwealth, who is going to be on your side?” Obama said to cheering supporters at Northeastern University.

To maximize the impact of his make-or-break speech, the president scheduled his appeal to be broadcast between two NFL playoff games.

Obama insisted that a vote for Brown would be a vote for the GOP establishment. “It’s hard to suggest he’s going to be significantly independent from the Republican agenda,” he said.

While painting Coakley as a public servant who would work hard for the people, Obama portrayed Brown as a politician who would side with special interests. He criticized Brown for opposing his plans to tax Wall Street. “She’s got your back; her opponent’s got Wall Street’s back,” Obama said.

As late as last month, Coakley enjoyed a sizable lead over Brown. But recent polls have shown the race has tightened, with some giving Brown a small lead.

Such a tight race in a state where Democrats outnumber Republicans by 3 to 1 has invigorated the GOP nationally — with some party leaders claiming Brown’s surge reflects voter discontent over Obama’s plans to reform the nation’s health-care system.

The health-care plan has dominated the Bay State race. Coakley has said she supports it, while Brown has made much of the fact that, if elected, he would be in position to rob the Democrats of the 60-vote majority needed to pass the legislation. With Obama stumping for his rival, Brown brought out some all-stars of his own at a rally in Wooster, about an hour’s drive from Boston.

Boston Red Sox hero Curt Schilling told the crowd of thousands that Brown was the right choice for the state. “You got to play the game. You’ve got to go out Tuesday, and you’ve got to vote for Scott Brown,” Schilling said.

jennifer.fermino@nypost.com