Hillary Clinton

Democratic presidential candidate Hillary Clinton arrives for a rally at East High School in Youngstown, Ohio on Saturday, July 30, 2016.

(Andrew Harnik, Associated Press)

Ohio proves to be a battleground state as the Republican and Democratic presidential candidates work to earn Buckeye votes. The Senate campaigns of Rob Portman and Ted Strickland are both working to get in touch with voters. Flags will fly at half-staff Monday to honor former Rep. Steve LaTourette. Read more in today's Ohio Politics Roundup, brought to you by Robin Goist.

Trump to talk about foreign policy in Youngstown: Instead of holding a conventional rally and perhaps focusing on the economic issues that affect the Mahoning Valley, Donald Trump will give a "major policy speech" Monday to an invitation-only audience at Youngstown State University, reports cleveland.com's Andrew J. Tobias.

The speech is scheduled to begin at 2 p.m. at YSU's Kilcawley Center and will be Trump's second appearance in the Mahoning Valley in the last six months. On the day before Ohio's primary election, he held a campaign rally at the Youngstown-Warren Regional Airport. While he lost the March 15 primary to Ohio Gov. John Kasich, Trump won every county in eastern Ohio, including Youngtown's Mahoning County.

Clinton to campaign in CLE: Just as Hillary Clinton discussed the economy during her visit to Youngstown on the heels of the Democratic National Convention, Clinton is expected to contrast her economic plan with Trump's on Wednesday in Cleveland, writes cleveland.com's Mary Kilpatrick. At John Marshall High School Wednesday afternoon, Clinton "will lay out the difference between Trump's vision for an economy that benefits himself and wealthy people like him and her vision for an economy that works for everyone, not just those at the top," according to a news release.

But even after Trump leaves Youngstown, his campaign plans to maintain presence in Ohio: Trump's campaign announced Friday the locations of 15 regional offices in Ohio, reports Tobias. "The 'victory offices' will be locations where the campaign can stage its political activity - coordinating volunteers, making phone calls and distributing signs and other materials - for the November election," Tobias writes.

Surprisingly, both Cuyahoga County, Ohio's most populous which cast the third-most votes for Mitt Romney in 2012, and Hamilton County, a swing county that cast the second-most votes for Romney, are absent from the list.

Clinton's campaign, by contrast, has 19 field offices in the Buckeye State, including one in Lakewood and one in Shaker Square, plus a central office in Columbus.

Talk about tax returns: Adding to the large stack of tax documents she has already made public, Clinton released her 2015 tax return Friday, reports cleveland.com's Kilpatrick. Her running mate, Tim Kaine, followed suit Friday and also released his tax returns from the past decade.

The Clinton campaign attacked Trump for failing to make his own tax documents public. Hillary for America communications director Jennifer Palmieri said in a news release that Trump "is hiding behind fake excuses and backtracking on his previous promises to release tax returns. He has failed to provide the public with the most basic financial information disclosed by every major candidate in the last 40 years. What is he trying to hide?"

Trump has said he will release his tax returns once a routine audit is complete, although many tax experts say this process does not bar anyone from making their documents public. Campaign chairman Paul Manafort confirmed last month that the Republican nominee will not release his tax returns before the election.

New ad attacks Portman on anti-heroin funding: "A new $1.1 million Ohio ad campaign from a labor union needles U.S. Sen. Rob Portman for voting against a budget bill that funded his plan to combat heroin addition," writes cleveland.com's Jeremy Pelzer. The 30-second ad from the American Federation of State, County and Municipal Employees will air in Cleveland, Dayton, Toledo and Youngstown through Aug. 22, according to an AFSCME release.

The ad criticizes Portman for voting against the $1.1 trillion "omnibus" spending bill that included money for his Comprehensive Addiction Recovery Act, or CARA, which Portman has touted as a success during his reelection campaign against former Ohio Gov. Ted Strickland.

Spokespeople for Portman said the senator lobbied to get that money in the omnibus spending bill in the first place and only voted against it because he felt other parts of the bill were wasteful.

But this will surely not be the last Senate race ad: Ohio's U.S. Senate race is the most expensive in the nation, according to the Center for Responsive Politics, which is largely due to outside groups, reports The Columbus Dispatch's Jessica Wehrman. These groups, such as AFSCME, alone have poured $33 million into the race - and it's not even Labor Day yet. The bulk of that total - nearly $19 million - has been spent opposing Strickland.

The campaigns themselves are working hard to court your vote: Increasingly sophisticated methods of data gathering allow both the Portman and Strickland campaigns to target and categorize voters, reports Wehrman. So even if you might not know much about either candidate, the chances are, their campaigns know about you.

Portman's campaign, for instance, held a "Super Saturday" event this past weekend. When campaign volunteers knocked on doors, they asked a series of questions and logged Ohioans' answers into a database with iPads or iPhones, so voters' interests were updated in real time. Even more, the questions they asked were targeted. Toledo voters received information about Portman's work on toxic algae and the Great Lakes, while voters in southeastern Ohio heard about his stance on coal.

"The research extends to television ad buys," Wehrman writes. "They know, for example, that a certain group of voters watches 'Love It or List It' in one part of the state, but that same group watches 'Property Brothers' in another corner."

Flags to fly at half-staff for LaTourette: To honor former Rep. Steve LaTourette, Gov. Kasich has ordered that flags on public grounds in Cuyahoga, Lake and Geauga counties, as well as at Ohio's Statehouse, fly at half-staff Monday, reports cleveland.com's Sabrina Eaton. The gesture, which will take place in much of the congressional district LaTourette represented in Congress for 18 years, coincides with a planned memorial service at University Circle United Methodist Church in Cleveland. The former congressman and Lake County prosecutor passed away of pancreatic cancer on Aug. 3 at his home in McLean, Virginia.

Ohio to appeal federal judge's ruling: U.S. District Court Judge Michael R. Barrett decided Friday to block Ohio from implementing laws that would defund Planned Parenthood, ruling the laws unconstitutional, writes cleveland.com's Robert Higgs.

While the judge acknowledged that Ohio could legally establish a policy to favor childbirth over abortion and bar use of public funding on non-therapeutic abortion procedures, the programs hit by these laws have nothing to do with abortion. Planned Parenthood cheered the ruling as a victory for access to health care services. The Ohio Department of Health and its director, Richard Hodges, did not have an immediate comment to the ruling, and the attorney general's office said the state will appeal.

U.S. Capitol to install Thomas Edison statue: A bronze statue of Milan, Ohio native Thomas Edison will become part of Congress' Statuary Hall collection on Sept. 21, writes Eaton. Each state contributes two statues, and Edison will accompany former President James Garfield, who hailed from Mentor. Zanesville sculptor Alan Cotrill made the new sculpture of Edison holding a light bulb, which went on display in Columbus' statehouse last year.

Eaton also explains the story of Congress rejecting Edison's first patented invention - an electronic voting system meant to record votes faster than the voice system.

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