In midterm elections, Republicans are running against ... Hillary Clinton. Still.

Chrissie Thompson and Deirdre Shesgreen | USA TODAY Network

COLUMBUS, Ohio – When Hillary Clinton lost her 2016 bid for the presidency, she retired from politics.

In Ohio, it's as if she never left.

More than 5,000 TV commercials this year have mentioned Clinton, all in the state's GOP primary for governor. Lt. Gov. Mary Taylor and Attorney General Mike DeWine each claim real-Republican status, using Clinton to try to cast doubt on their opponent's conservative credentials.

As a U.S. senator, "D.C. DeWine voted with Hillary Clinton 962 times" in six years, says one TV commercial from Taylor's campaign. The Senate roll-call voice then reads out "Aye" for both Clinton and DeWine on immigration, spending and gun control bills.

GOP ads around the country echo the Taylor campaign's use of Clinton. That's desperate, Democrats said, accusing Republicans of pointing to a defeated presidential candidate to avoid talking about their party's short list of accomplishments since they took control of Washington.

In a GOP primary, it's actually a smart strategy, said Jennifer Duffy, who analyzes governor and Senate races for the non-partisan Cook Political Report.

"The end goal is to taint somebody as not conservative enough, and there are limited ways to do that," she said. "If you tie them to an unpopular Democrat, that helps really hammer home that message."

In total, nearly 13,000 TV commercials Jan. 1 through April 24 mentioned or showed a photo of Clinton, according to data compiled for the USA TODAY NETWORK by Kantar Media's Campaign Media Analysis Group.

Republicans in the Ohio governor's race ran the most ads, followed by West Virginia Republicans running for governor and the GOP candidates for Indiana Senate.

Only former president Barack Obama has appeared in more ads. Clinton's total tops that of House Minority Leader Nancy Pelosi, who has been mentioned in nearly 10,000 commercials in 2018.

The strategy could forecast a slew of anti-Clinton ads this fall in states President Trump won handily as Republicans try to beat back Democrats' push to regain control of Congress. In the same way, Democrats will try to tie GOP candidates to Trump in the states where Trump's margin was thin or where Clinton won, Duffy said.

'Now she's called you backwards'

Republican strategists said Clinton remains a deeply polarizing figure, even in defeat. Clinton proved that herself in March. During a trip to India, the Democratic nominee said she won parts of the USA that were more economically vibrant, while Trump won in the Midwest and other places by appealing to voters who want to move “backwards.”

“His whole campaign — ‘Make America Great Again’ — was looking backwards,” Clinton said in response to a question about how Trump won. “You know, you didn’t like black people getting rights, you don’t like women, you know, getting jobs, you don’t want, you know, to see that Indian American succeeding more than you are.”

National Republicans pounced on Clinton’s comments. The GOP’s Senate campaign committee launched a digital ad campaign targeting 10 Senate Democrats in states that Trump won with spots reminding voters of their support for Clinton.

“She called you ‘deplorable,' ” one spot reminded voters in Missouri. “Now she’s called you ‘backwards.’ … And if Claire McCaskill had her way, Hillary Clinton would be president.”

McCaskill is one of the most vulnerable incumbent Senate Democrats up for re-election this year, running in Missouri, where Trump won by 19 percentage points. The ads also ran in Ohio, Montana and elsewhere — sending Democrats into a scramble to distance themselves from Clinton.

“Whenever (Clinton) inserts herself into the conversation and continues to make comments that Trump voters are backwards or deplorable, it’s a reminder to folks in red states that supported him that your sitting senator sided with her over the president you voted for,” said Katie Martin, a spokeswoman for the National Republican Senatorial Committee.

Republicans are the ones looking backward, Democrats said, because the GOP has nothing else to talk about as Republicans try to maintain their grip on power.

“It’s obvious that Republicans are desperate,” said David Bergstein, a spokesman for the Democratic Senatorial Campaign Committee. The GOP tax cut isn’t as popular as Republicans hoped, he said, and Republicans haven’t accomplished much else. Moderate and independent voters may be worried about losing health care coverage or paying more under GOP proposals.

“This election will be a referendum on how Republicans have used their control of Washington to make life more difficult and expensive for working families,” Bergstein said.

Using Clinton makes it possible for GOP candidates to change the conversation. Voters know her, and it's easy to associate lesser-known candidates with what voters know — and don't like — about Clinton.

"She is a loser," said Andrew Downs, director of the Mike Downs Center for Indiana Politics. "Candidates are going to want to tie Democratic candidates to the person who lost. 'You rejected her. You should reject this person, too.' "

In each of the states where negative ads mentioning Clinton aired — Ohio, West Virginia, Indiana, Mississippi and Idaho — she lost badly to Trump in 2016.

She lost by 42 points in West Virginia, which has a crowded GOP primary for U.S. Senate. Clinton was a natural tool in ads against U.S. Rep. Evan Jenkins, a former Democrat who switched party affiliations in 2013.

Although Jenkins backed Obama's successful 2008 run for president, he attended an economic policy town hall meeting in 2007 with Clinton, who ran against Obama. Ads accuse Jenkins of participating in a campaign rally for Clinton.

Jenkins is fighting back by using Clinton in his own ads. One spot shows her comment about Trump's campaign moving "backwards." "It's Hillary who's got it backwards," Jenkins says. "I approve this message to help President Trump move America forward."

'Ghost of some elderly' retiree

Trump and Republicans in Congress may struggle with national approval, but there's no doubt where voters stand on Clinton, Republican strategists said. So Democrats may see Clinton-focused attacks this fall.

Take Sen. Sherrod Brown of Ohio. Polls show Brown leading his re-election bid. Republicans could try to link him to Clinton, who lost Ohio by 8 points in 2016.

"For all the ups and downs across the country in polling, Ohio was a state for Donald Trump that he always had on lock," said Ethan Zorfas of Axiom Strategies, the GOP firm behind Taylor's anti-Clinton gubernatorial campaign in Ohio. "Democrats across the state of Ohio are going to have to weigh the support they gave to Hillary Clinton in 2016. It could affect the Senate race."

Brown appeals to Trump's working-class voters in Ohio, in part because of his long-standing concerns about free trade. When Trump was elected, Brown wrote him a letter suggesting they collaborate on trade. Republicans, Duffy said, will try to tell voters: "Really, he was with Hillary and Obama. He's not who he says he is."

Even some conservatives disapprove of that strategy.

Commentator Tucker Carlson of Fox News derided Republicans for running against "the ghost of some elderly retired nominee from last cycle" instead of telling voters what they would do with a two more years in power. "Hillary Clinton doesn't run anything anymore — she doesn't represent the modern Democratic Party," he said last week.

Clinton's comments, such as the "backwards" remark, show she never actually left politics, said Rob Secaur, executive director of the Ohio GOP. "If Hillary Clinton isn't the leader of the Democratic Party, who is?"

Contributing: Fredreka Schouten

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