President Obama’s $447 billion jobs plan foundered in the Senate on Tuesday night, as a unified Republican caucus and a pair of Democrats joined to deny the proposal the 60 votes needed to allow it to proceed to full consideration.

Obama will now use Republican opposition as part of a campaign to paint the GOP as obstructionists blocking his efforts to improve the economy while offering no alternative to create jobs.

“Tonight’s vote is by no means the end of this fight,” the President said in a statement issued after the vote. “In the coming days, Members of Congress will have to take a stand on whether they believe we should put teachers, construction workers, police officers and firefighters back on the job.”

Although a number of Democrats who will face tough reelection efforts next year had wavered in support, only two voted not to allow the measure to advance, a symbolic victory for Obama and Senate Democratic leaders, who knew that strong Democratic opposition would be an embarrassment for the White House.

Senior White House officials said the vote was the first step to spur action on job creation. Next, they said, Obama will work with Senate leaders to break the jobs bill down into its parts — which polls show are very popular with voters — and challenge Republicans to reject each individually.

“Ultimately, the American people won’t take “no” for an answer,” Obama said. “It’s time for Congress to meet their responsibility, put their party politics aside and take action on jobs right now.”

Democrats believe that Republicans will find it hard to oppose an extension of a payroll tax holiday —worth about $1,000 a year to the average family.

“This will just be the first act in a long-term play here over the next couple of months,” a senior White House official before the Tuesday vote. “Either, one, we get a lot of this done and it’s good for the economy, which is our preference. Or we don’t, and the American people know why.”

A senior Senate Democratic aide confirmed that Sen. Charles E. Schumer (D-N.Y.) has been shopping a plan to package an infrastructure bank to fund transportation improvements, an ele­ment of Obama’s bill, with a proposal favored by many Republicans to offer corporations a tax break if they return offshore earnings to the United States.

Republicans said they have always preferred negotiating the package piece by piece and said the vote was an effort to turn the debate into a political bludgeon.

They note that both chambers will vote this week on new free-trade agreements with Colombia, Panama and South Korea, deals supported by both parties and advocated by Obama for months.

The House this week will also mull a plan to provide new training dollars for veterans entering the workforce, similar to part of Obama’s plan that would give businesses tax credits to hire vets.

“This whole exercise, by their own admission, is a charade that’s meant to give Democrats a political edge in an election that is 13 months away,” Senate Minority Leader Mitch McConnell (R-Ky.) said of the vote on the package.

Obama has barnstormed the country to encourage a congressional vote on the American Jobs Act as a whole. He went Tuesday to a union training center in Pittsburgh, where he called the vote a “moment of truth” for the Senate.

Besides payroll tax cuts for workers and small businesses, the package includes tax credits for businesses that hire veterans and the long-term unemployed, funds for road and school construction, and dollars for hiring teachers and first responders.

“Today’s the day when every American will find out exactly where their senator stands on this jobs bill,” Obama said in Pittsburgh. “Any senator who votes no will have to look you in the eye and tell you what exactly they are opposed to.”

But Republicans will argue the Senate defeat shows Obama’s ability to harness the bully pulpit to compel legislative action has waned as his popularity has fallen.

Democratic Sens. Ben Nelson (Neb.) and Jon Tester (Mont.), who each face tough reelection bids, voted against the bill.

The vote was 50 to 48 early in the evening but was held open for a late-arriving Jeanne Shaheen (D-N.H.). She voted yes, making the final tally 50 to 49 after Reid switched his yes vote to no for procedural reasons. It lets him more easily bring the bill up for a potential new vote in coming days.

Republicans remained unified against the package even after Democrats tried to make the vote a choice between workers and the wealthy by swapping Obama’s suggestion that the package be funded by tax increases on those making more than $250,000 for a 5.6 percent tax on millionaires.

In so doing, Senate leaders tried to tap into widespread public discontent over the growing income gap between rich and poor, frustrations that have given rise to weeks of protests in New York, Washington and elsewhere.

Those protests arrived at the Capitol on Tuesday, as a group affiliated with the Occupy D.C. movement unfurled banners in the Senate’s Hart Office Building calling for an end to overseas wars and for increased taxes on the rich. Six were arrested.

Staff writers Lori Montgomery and Felicia Sonmez contributed to this report.