Michigan Gov. Gretchen Whitmer (D) expanded her lead over Republican challenger Tudor Dixon to 16 points in a poll from the Detroit Free Press released on Thursday.

Fifty-five percent of likely voters said they would support the current governor, compared to the 39 percent who said they would back the Trump-endorsed GOP candidate, the poll found. Six percent were undecided.

Whitmer’s lead has grown by 5 points since an August Free Press poll that showed her at 50 percent and Dixon at 39 percent.

Some Republican strategists have voiced concerns recently that hard-line GOP candidates, like Dixon, may be alienating voters. Dixon said in an interview in August that she only supported abortion exceptions if the life of the mother is in danger and suggested that rape victims could heal through giving birth.

Abortion was a top issue among likely Michigan voters in the Free Press poll, tied with inflation at 24 percent.

Whitmer is also leading Dixon in favorable ratings. While 52 percent of likely voters rated Whitmer favorably, only 24 percent said the same of Dixon. Both candidates had 44 percent unfavorable ratings.

The current governor is drawing on bipartisan support for her reelection bid, with more than 150 Michigan Republicans launching Republicans for Whitmer this month.

The Free Press poll was conducted by EPIC-MRA of Lansing, Mich., from Sept. 15 to 19 with 600 likely voters and had a margin of error of plus or minus 4 percentage points.