Washington (CNN) More Americans believe special counsel Robert Mueller's investigation is justified than politically motivated, according to a CBS News poll released Wednesday, the first time the survey has found more Americans hold that belief.

According to the poll, the percentage of Americans who believe the investigation is justified stands at 50% while 45% believe it is politically motivated. The numbers represent a change from where they stood in late November, when CBS found that 46% of Americans thought the investigation was justified and 51% believed it was politically motivated.

Helping drive the numbers is an increase among Democrats who now say the investigation is justified. In the January poll, CBS found that 84% of Democrats view the probe that way, up from 74% in November. Among independents, 46% told CBS that they thought the investigation was justified, up from 44% in November, though the number of those who believed the investigation was politically motivated -- 52% in November, 47% in January -- tightened.

Meanwhile, the views among Republicans has stayed consistent: a mere 14% of Republicans viewed the investigation as justified in CBS's new poll.

In the period between CBS's two polls, Mueller's investigation has produced a wave of bombshell headlines, from Michael Cohen, Trump's former lawyer, admitting he lied to Congress about a Moscow project to a New York Times report that the FBI opened an investigation into whether Trump was working on Russia's behalf to the "extraordinary lengths" to which Trump went to keep his administration in the dark about his meetings with Russian President Vladimir Putin.

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