Washington CNN  — 

Hillary Clinton’s lead over her would-be GOP foes has slipped in three critical swing states as the growing controversy over her email use has dominated coverage of the likely Democratic presidential candidate.

Former Florida Gov. Jeb Bush scrapes past Clinton with a three-point lead, still within the margin of error, in a hypothetical head-to-head matchup in Florida, according to a Quinnipiac University poll released Tuesday. Clinton had a one-point edge in the Florida dead heat Quinnipiac reported in early February.

The last two months have also erased Clinton’s previously double-digit lead over every other potential GOP contender for the presidency in Florida, Ohio and Pennsylvania.

Sen. Rand Paul, the libertarian-leaning Republican from Kentucky, is now the man to beat in Ohio after he narrowed his margin against Clinton to just a five-point deficit, according to Tuesday’s poll. Paul, who is expected to announce his bid for the presidency next week, trailed Clinton by 12 points in Quinnipiac’s early February poll.

Every potential 2016 Republican contender included in the February survey has since gained on Clinton in Ohio – even if by just two points, like in Bush’s case.

Paul is also winning over Pennsylvanians, trimming his 9-point deficit to a virtual tie, landing 45% of support to Clinton’s 44% in the state.

Clinton remains a strong favorite – especially so early on – against virtually every other potential Republican contender for president in the three battleground states.

But it’s clear Clinton’s email scandal – first that she exclusively used private email housed on a private server as secretary of state, and then that she deleted all the emails on that server – has leveled a hit to Clinton’s public image and trustworthiness, according to the Quinnipiac poll.

About half of voters in all three states say Clinton is not honest and trustworthy – by a 5-to-4 margin in Florida and Pennsylvania, with a closer split in Pennsylvania.

And Clinton’s favorability rating has also slipped in Florida – to 49% from 53% – and Pennsylvania – now at 48% from 55% – though she still gets more favorable reviews than all of her would-be Republican opponents, except for Bush and Florida’s Sen. Marco Rubio in that state.