Hillary Rodham Clinton will jump the primary queue for a campaign rally Thursday in Ohio, looking to the state that kept her campaign alive in 2008 to now give her a boost amid sliding poll numbers and a looming challenge by Vice President Joseph R. Biden.
Interrupting her family beach vacation in New York’s tony Hamptons, Mrs. Clinton sought out the friendly terrain of Cleveland for a late summer campaign and fundraising stop where she hopes to not suffer more questions about the growing controversy of her exclusive use of a private email account for official business as secretary of state.
The former first lady, senator and top diplomat will lead a grass-roots organizing rally at Case Western Reserve University in Cleveland, where she’ll urge supporters to sign a “Commit to Vote” card that pledges their support in the state’s primary next year, accordion to the Clinton campaign.
Mrs. Clinton later will attend a private $2,700-a-ticket fundraiser at the home of Cleveland socialite Judi Embrescia.
The excursion to Cleveland, where Republicans will hold their national convention and pick their presidential nominee next summer, also will provide an opportunity for Mrs. Clinton to present herself as the presumptive Democratic nominee and train her attacks on GOP rivals.
The Buckeye State has always come through for Mrs. Clinton. In 2008, her win in the Ohio primary after a series of losses kept her in the hard-fought nominating race that she ultimately lost to then-Sen. Barack Obama.
She again turned to Ohio, which holds its 2016 primary election in mid-March after about 20 other states have already voted, as she faced a surge by Sen. Bernard Sanders in early-voting states.
Mr. Sanders, the Vermont independent and avowed socialist who is running for the Democratic nomination, beat Mrs. Clinton by 7 points, 42 percent to 35 percent, in a poll released Tuesday of likely Democratic voters in New Hampshire’s first-in-the-nation primary.
Mr. Sanders had gained 30 points in the New Hampshire poll since April.
“The main story in New Hampshire is how universally popular Sanders has become with the Democratic electorate,” said the pollsters at the Democratic-leaning Public Policy Polling. “Meanwhile Hillary Clinton’s favorability numbers have taken a little bit of a hit.”
The survey mirrored other polls that have shown voters losing trust in Mrs. Clinton as she struggles with the email controversy, including new questions about her handling of classified documents which has prompted a federal investigation and conceivably could result in criminal charges.
Mrs. Clinton’s favorability score had dropped to 63 percent favorable/25 percent unfavorable from 78 percent favorable/10 percent unfavorable in April. Mr. Sanders’ score soared to 78 percent favorable/12 percent unfavorable in the new poll.
She’s also taken a hit in Ohio, where a Quinnipiac University poll last week showed her leading all of her primary rivals but with 60 percent of Ohio voters saying they don’t find her “honest and trustworthy.”
In general election match-ups, the poll showed her with thin leads over Republican candidates former Florida Gov. Jeb Bush and billionaire businessman Donald Trump, and slightly trailing Sen. Marco Rubio of Florida.
Mrs. Clinton remains the odds-on favorite to win the nomination, but the email controversy and her clumsy handling of the issue on the campaign trail has caused concerns among Democrats that she can’t win the White House and sparked excitement about a possible run by Mr. Biden.
Mr. Biden has been inching closer toward another White House run, getting the go-ahead from Mr. Obama and huddling this week with top advisers to explore his options. He would be getting in the race relatively late, but the vice president would benefit from near universal name recognition and a ready-made campaign organization waiting in the wings.
Prominent Democratic bundlers already have lined up to support Mr. Biden, promising to quickly raise tens of millions of dollars to jump-start his run before the end of the year.
A run by Mr. Biden, who ran unsuccessfully for the Democratic presidential nomination in 1988 and 2008, would not only test the allegiance of the party establishment but likely force Mr. Obama to choose between his vice present and his former secretary of state.
Mrs. Clinton got some good news Tuesday from a Suffolk University poll that showed her retaining a huge lead in Iowa. Likely voters in the Iowa Caucuses, the country’s first nominating contest, gave Mrs. Clinton a 34-point lead over Mr. Sanders, 54 percent to 20 percent.
Mr. Biden finished in third place in the poll with 11 percent of the vote.
“There is a fierce loyalty to Hillary Clinton among likely Democratic caucus-goers in Iowa,” said David Paleologos, director of the Suffolk University Political Research Center in Boston. “Despite reports suggesting her vulnerability, these Democratic voters say they don’t believe she broke the law. They are sticking by her in large numbers, even though a majority believes the email scandal will hurt her in the general election.”
However, 52 percent of Iowa Democrats told the pollsters that they think the email controversy would hurt Mr. Clinton in the general election.