Hillary Clinton leads Donald Trump by 10 percentage points, 46-36, among registered voters in Wisconsin, according to a new poll.

The Marquette University Law School poll shows Clinton expanding her lead by 4 percentage points, up from 43-37, in July.

Clinton's lead is even larger among likely Wisconsinite voters surveyed. The Democratic nominee's advantage over Trump is 15 percentage points, 52-37, among likely voters in Wisconsin.

Libertarian nominee Gary Johnson earned 9-percent support among likely voters and 10 percent among registered voters surveyed.

Charles Franklin, the poll's director, said the poll numbers look similar to the 2008 election. But leading Republicans who hail from the Badger State — including Gov. Scott Walker, House Speaker Paul Ryan, and Republican National Committee chairman Reince Priebus — hoped the state would look purple in 2016.

Incumbent GOP Sen. Ron Johnson trails former Democratic Sen. Russ Feingold by 6 percentage points among registered voters, 49-43, and Johnson is down 11 points to Feingold among likely voters.

Contributing to the Democrats' growing leads in Wisconsin may be voter enthusiasm on either side of the aisle. The poll reveals that Wisconsin Democrats' commitment to voting in November is rising, while Republicans' intent to vote is slipping.

The Marquette University Law School poll surveyed 801 people, including 683 likely voters, from August 4-7 with a margin of error of 4.6 percentage points for the full sample and 5 points for the likely voter sample.

Fewer than 90 days remain until the election.