WASHINGTON -- Another new poll has found Democrat Katie McGinty surging into a late summer lead over Republican Sen. Pat Toomey in the critical Pennsylvania senate race.

A Quinnipiac University survey released Thursday morning found McGinty leading Toomey, 47 percent to 44 among likely Keystone State voters. That's within the poll's margin of error, but suggests a far tighter contest than pollsters found earlier this summer, when Toomey had solid leads.

The new poll is the third in the past week showing McGinty, Gov. Wolf's former chief of staff, with a small lead a few weeks ahead of Labor Day, when campaigns typically kick into high gear. Her rise coincides with Hillary Clinton's sharp gains in Pennsylvania in the wake of the Democratic National Convention.

Toomey's 44 percent support is similar to the 42 percent backing Republican presidential nominee Donald Trump registered in the same poll. But while Clinton had 52 percent support, McGinty -- who has never held elected office and is still introducing herself to many voters -- has won less backing.

The poll shows sharp disparities among races and genders. Toomey, seeking his second senate term, won 51 percent of white voters, but only 12 percent of non-whites. Women favor McGinty 52 - 38, while men support Toomey 51 – 41.

Pollsters have cautioned that surveys at this point may still be picking up the effects of the Democratic convention, which was held in Philadelphia and dominated media coverage. The poll was conducted immediately after the convention, from July 30 to Aug. 7, and surveyed 815 Pennsylvania voters. It has a margin of error of 3.4 percentage points.

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