Hillary Clinton is leading Donald Trump in seven swing states in a Ballotpedia poll. | AP Photo Battleground bloodbath: Clinton leads Trump in 7 swing states

Hillary Clinton is polling higher than Donald Trump in seven swing states, holding leads ranging from 4 to 17 percentage points, according to a poll released Wednesday.

Of the seven states polled by Ballotpedia, Clinton’s lead was smallest in Iowa, where registered voters who responded to the poll preferred her by 4 points. The former secretary of state’s largest lead came in Michigan, a traditionally Democratic-leaning state where Trump has said he could compete in November. Clinton leads the Manhattan billionaire there by 17 points, 50 percent to 33 percent.

Clinton also holds double-digit leads over Trump in Florida (14 points), Pennsylvania (14 points) and North Carolina (10 points). Respondents preferred her to Trump by 9 points in Ohio and 7 points in Virginia.

Clinton maintained her advantage when respondents were offered a third option, Libertarian candidate Gary Johnson, although her leads shifted slightly. In a three-way race, Clinton’s lead among those polled dropped to just 3 points in Iowa and 6 points in North Carolina. But Johnson’s introduction as an option increased the former secretary of state’s lead to 15 points and 8 points in Pennsylvania and Virginia, respectively.

Ballotpedia also polled Clinton in presidential matchups against two other prominent Republicans, House Speaker Paul Ryan and Ohio Gov. John Kasich, even though Trump has been the GOP’s presumptive nominee since early May and both men have disavowed interest in running. Kasich polled well against the former secretary of state, besting her in five states: Iowa, Michigan, Ohio, Pennsylvania and Virginia. Ryan polled better than Clinton in three states: Iowa, Ohio and Virginia.

The Ballotpedia poll was conducted among active registered voters via landlines and cellphones from June 10-22, much longer than the usual three to five days for a statewide poll. Interviewers reached 596 respondents in Florida, 601 in Iowa, 612 in Michigan, 603 in North Carolina and 601 in Pennsylvania, all with a margin of error of plus or minus 4 points. The poll also reached 617 registered voters in Ohio and 612 in Virginia, each with a margin of error of plus or minus 3.9 points.

Ballotpedia, an online political encyclopedia whose staff covers politics and elections, is sponsored by the nonprofit organization the Lucy Burns Institute.