Hillary Clinton's steadily dropping poll numbers have resulted in some particularly troubling survey results this week for the Democratic frontrunner. Wednesday, CNN announced that its new poll found that Donald Trump is within striking distance of Clinton in a hypothetical general election matchup. Thursday, the new Quinnipiac Swing-State Polls found Hillary trailing Republican rivals in three key states and being outperformed overall by Joe Biden.

Quinnipiac found that while Clinton and Trump are currently "clear winners" in the primaries in Florida, Ohio, and Pennsylvania, general election matchups tell a different story. Clinton loses a majority of the head-to-heads with top Republican candidates in all three states, while Biden "runs as well as or better" than Clinton against potential opponents. As for Trump: he consistently performs the worst in all three swing-states when compared with Jeb Bush and Marco Rubio.

A possible explanation for Clinton's and Trump's poor performance in head-to-head matchups: Quinnipiac underscores that both candidates have the "worst overall favorability ratings among all voters of any of the leading candidates, and the lowest scores for being honest and trustworthy."

Below are the key matchup results by state.

FLORIDA: Both Clinton and Sanders lose to all three Republicans, while Biden pulls out a win against Trump.

• Clinton loses to Bush (38/49), Rubio (39/51), and Trump (41/43).
• Biden loses to Bush (38/51) and Rubio (42/48), beats Trump (45/42).
• Sanders loses to all three (35/54, 36/52, 41/45, respectively).

OHIO: Again, Biden outperforms Clinton and Trump fares the worst out of the three Republicans.

• Clinton beats Bush (41/39), loses to Rubio (40/42), and beats Trump (43/38).
• Biden beats all three (42/39, 42/41, 48/38).
• Sanders loses to Bush (36/42) and Rubio (34/42), beats Trump (42/40).

PENNSYLVANIA: Bush and Rubio beat all three Democrats; Trump loses to all three.

• Clinton loses to Bush (40/43) and Rubio (40/47), beats Trump (45/40).
• Biden loses to Bush (42/43) and Rubio (41/44), beats Trump (40/48).
• Sanders loses to Bush (36/44) and Rubio (33/45), beats Trump (44/41).

A candidate's viability in Florida, Ohio, and Pennsylvania is considered essential because, as Quinnipiac notes, "since 1960 no candidate has won the presidential race without taking at least two of these three states."