Johns Hopkins is more than halfway to its $4.5 billion fundraising goal, the university announced Wednesday, with the money helping to support initiatives that include urban revitalization and global health.

More than 162,000 donors have helped Hopkins meet the halfway mark earlier than officials had previously expected, in spring 2014. The $4.5 billion fundraising goal is among the biggest such efforts in the country and the largest for the Johns Hopkins University and Johns Hopkins Hospital.

The fundraising campaign, called Rising to the Challenge, had netted close to $2 billion during a "quiet phase" that began in January 2010 until it was formally announced this May. The institution expects to meet the $4.5 billion goal by 2017.

The quiet phase included a $350 million gift from New York Mayor Michael R. Bloomberg, a Hopkins alumnus. Announced early this year, it was the largest donation to Hopkins in its history. The Bloomberg donation will go toward $100 million in student aid and to endow 50 professor positions.

The campaign is expected to pay for a total of 300 endowment-funded professorships, thousands of scholarships, new graduate fellowships and five interdisciplinary "signature initiatives" of global health, individualized health, the science of learning, water and the American city. More than 260 donors have committed $1 million or more.

With the help of the more than $2.25 billion raised so far, researchers at The Science of Learning Institute are studying genetic contributions to learning ability and attempting to tackle urban problems of crime and health issues through the Institute for the American City.

Hopkins reached the milestone in early November.

"This is a significant milestone on a journey to realize our vision of what Johns Hopkins can be and what it can do for humanity," Hopkins president Ronald J. Daniels said in a statement.

A previous fundraising campaign that ended in 2008 raised $3.7 billion.

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