Story highlights Hillary Clinton has opened up commanding leads over Donald Trump, according to new NBC/WSJ/Marist polls.

The polls find her ahead among registered voters in Colorado, North Carolina, Florida, and Virginia.

Washington (CNN) Hillary Clinton has opened up commanding leads over Donald Trump in several critical battleground states, including North Carolina and Colorado, according to a new poll Friday.

The results represent increasing margins for Clinton in each of those four states, compared with polling conducted before the conventions and all the leads are outside each poll's margin of sampling error. The polls also tested four-way matchups including Gary Johnson and Jill Stein and found that the margin between Clinton and Trump holds when the third party candidates are included.

The polls were conducted between August 4 and this past Wednesday, a particularly bad post-convention stretch for Trump that found him embroiled in a fight with Khan family and making controversial comments about the Second Amendment and Hillary Clinton.