WASHINGTON (CBSNewYork) — Vice President Joe Biden says he won’t run for president in 2016.

His decision finalizes the Democratic Party’s field of White House candidates and sets Biden on a glide path toward the end of his decades-long political career.

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Biden spent months deliberating with his family and political advisers about a potential late entry to the Democratic primary.

But he also said he might not be emotionally ready to run after his 46-year-old son Beau died of brain cancer in May.

“I know from previous experience that there’s no timetable for this process,” Biden said. “The process doesn’t respect or much care about things like filing deadlines or debates and primaries and caucuses.”

Biden’s decision bolsters Hillary Rodham Clinton’s standing in the Democratic primary by sparing her a challenge from the popular vice president.

“But while I will not be a candidate, I will not be silent. I intend to speak out clearly and forcefully, to influence as much as I can where we stand as a party and where we need to go as a nation.”

Encouraged by Democrats seeking an alternative to Clinton, Biden had spent the past several months deeply engaged in discussions with his family and political advisers about entering the primary. Yet as the deliberations dragged on, Democrats began publicly questioning whether it was too late for him to run, a notion that hardened after Clinton’s strong performance in last week’s Democratic debate.

Notably, Biden did not endorse Clinton or any of the other Democratic candidates. Instead, he used the announcement to outline the path he said Democrats should take in the 2016 campaign, including a call for them to run on Obama’s record.

Biden said he believes Obama has led the country from “crisis to recovery and we’re now on the cusp or resurgence. I’m proud to have played a part in that. This party, our nation will be making a tragic mistake if we walk away or attempt to undo the Obama legacy. The American people have worked too hard, and we’ve come too far for that.”

As CBS2’s Craig Boswell reported, even though Biden is out, he said he will be a large figure in the race for the White House.

“While I will not be a candidate, I will not be silent,” he said.

He even took a shot at Democratic front runner Hillary Clinton who said last week that the Republicans were her greatest enemy.

In what could have been a campaign speech, Biden deplored the influence of unlimited contributions on politics, called for expanding access to college educations and called on Democrats to recognize that while Republicans may be the opposition, they are “not our enemy.”

“Four more years of this kind of pitched battle might be more than this country can take,” he said.

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Wednesday’s announcement was a letdown for Biden supporters who had pleaded with him to run, and in increasingly loud tones as his deliberations dragged on through the summer and into the fall.

For months, the 72-year-old Democrat made front pages and appeared on cable news screens as pundits mused about his prospects and Clinton’s perceived vulnerability. A super political action committee, Draft Biden, was formed with the explicit goal of getting him into the race.

At the White House, aides and longtime Biden loyalists had prepared for a potential bid, putting together a campaign-in-waiting should he decide to jump in. Last week one of those aides, former Sen. Ted Kaufman, wrote an email to former Biden staffers laying out the potential rationale for a Biden run and promising a decision soon.

Biden spoke personally to many supporters. As speculation about his plans reached a fever pitch, he kept up an intense schedule of public appearances, seemingly testing his own stamina for an exhausting presidential campaign.

But he also continued to broadcast his reluctance amid doubts that he and his family were emotionally ready in the wake of Beau Biden’s death.

In a September appearance on “The Late Show,” Biden told host Stephen Colbert he was still experiencing moments of uncontrollable grief that he deemed unacceptable for a presidential aspirant. “Sometimes it just overwhelms you,” he said, foreshadowing his ultimate decision.

Biden would have faced substantial logistical challenges in deciding to mount a campaign this late in the primary process.

Both Clinton and Vermont independent Sen. Bernie Sanders have been in the race since April — giving them a powerful head start in fundraising, volunteers, endorsements and voter outreach. Top Democratic operatives and donors already committed to Clinton would likely have had to defect to Biden in order for him to have viable shot at the nomination.

Clinton called Biden a good friend and a great man. She could have the most to gain from Biden’s decision. The latest national poll shows her lead over Sanders jumps to a 25 point margin when Biden is taken out of the mix.

Having decided against a final presidential campaign, Biden now approaches the end of his long career in politics.

A month after being elected to the Senate in 1972 at age 29, Biden’s wife and baby daughter died when their car collided with a tractor-trailer. Biden considered relinquishing his seat, but instead was sworn in at the hospital where his sons, Beau and Hunter, were recovering.

Over six terms in the Senate, he rose to become chairman of the Senate Judiciary and Foreign Relations committees, developing broad expertise in global affairs and a reputation for a plainspoken, unpredictable approach to politics.

Biden twice ran for president. His most recent attempt in 2008 ended after he garnered less than 1 percent in the Iowa caucuses. His first run in 1987 ended even more quickly, following allegations he plagiarized in some speeches from a British politician.

He has not yet detailed his post-White House plans, but has told friends he has no plans to retire in a traditional sense. Although unlikely to again seek elected office, friends and aides say Biden has previously discussed starting a foundation, launching an institute at the University of Delaware or taking on a role as a special envoy and elder statesman if called upon by future presidents.

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