Sen. Bob Menendez led Republican challenger Bob Hugin by 12 percentage points in a poll released by Stockton University on Friday, a sharp change from an Oct. 1 survey that had showed Menendez's lead at just 2 points and led to criticism of the survey.

Menendez led Hugin 51 percent to 39 percent among likely voters, according to the new poll taken last Friday through Wednesday. The Oct. 1 poll had Menendez at 45 percent and Hugin at 43 percent.

As with earlier surveys by other universities, Stockton found more people with an unfavorable opinion of Menendez outnumber those with a favorable opinion 42 percent to 22 percent. But voters have an even lower opinion of President Donald Trump, with 52 percent saying he does a poor job, 10 percent a fair job, and 37 percent a good or excellent job.

Asked to pick the biggest factor in deciding their votes from choices offered, 36 percent chose "control of the Senate," 35 percent chose "President Donald Trump," 19 percent chose "Menendez's former corruption charges" and 4 percent said "Hugin's actions regarding drug prices."

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Menendez was "severely admonished" by the bipartisan ethics committee in April after criminal charges including bribery ended in a hung jury, partial acquittal by the judge and a decision by the Justice Department not to attempt another trial.

Hugin was the chairman and chief executive of Celgene Corp., which has been criticized by the Food and Drug Administration as well as Menendez and his supporters for trying to thwart competition from companies trying to make cheaper generic versions of its cancer-fighting drugs.

Compared to the October survey, Stockton found that Menendez's support among Democrats grew from 80 percent to 87 percent, and Hugin's lead among independents dropped from 13 points to 7.

The October survey was criticized by Menendez's pollster, Joel Benenson, for only including 24 people aged 18-29 and only 24 Latinos in a sample of 578. The new poll, of 589 likely voters, included 68 people aged 18-29, and 44 who consider themselves Latino.

The Stockton poll had a margin of error of plus minus 4 percentage points.