NEW YORK (AP) — Two months ahead of his first trip to the U.S., Pope Francis’ approval rating among Americans has plummeted, driven mostly by a decline among political conservatives and Roman Catholics, according to a new Gallup poll released Wednesday.

Fifty-nine percent of Americans said this month they had a favorable view of the pope, compared to 76 percent in February 2014, Gallup reported. The share of Americans who disapproved of the popeincreased from 9 percent to 16 percent in the same period. The changes were most dramatic among political conservatives, whose opinion of Francis nosedived by 27 percentage points to 45 percent. Among Catholics, Francis’ approval dropped by 18 percentage points to 71 percent.

The survey was conducted from July 8 to 12, three weeks after the pope released his bombshell teaching document proclaiming climate change largely man-made and excoriating an economic system he said drives global warming and exploits the poor. The survey of more than 1,000 adults had a margin of error of plus or minus 4 percentage points.

When the poll was under way, Francis, the first Latin American pope, was on a homecoming tour through South America that especially unsettled conservatives.

In his July 9 speech in Bolivia — an address that the Rev. Jim Martin, editor at large of the Jesuit magazine America, called Francis’ most revolutionary so far — the pope called for radical reform of the global economy and solidarity with the poor, while naming labor, lodging and land as “sacred rights.”