U.S. Sen. Susan Collins of Maine has become the latest Republican to disavow GOP presidential nominee Donald Trump. From her op-ed in today's Washington Post:

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Republican Donald Trump may be hedging, but Democrat Hillary Clinton has committed to the three presidential debates as scheduled on Sept. 26, Oct. 9 and Oct. 19, her campaign said Monday. Meanwhile, according to Politico.com:

The venues that will host the presidential debates are drawing up plans for a three-person forum that would provide a lectern for a third-party candidate to stand on stage next to Hillary Clinton and Donald Trump.

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While you wait for Michael Phelps in the 200-meter butterfly tonight, keep an eye on Wisconsin and U.S. House Speaker Paul Ryan. From the Associated Press:

Paul Nehlen's star rose after Trump praised him last week on Twitter, then later pointedly withheld his endorsement of Ryan. Trump relented just three days later after coming under criticism from GOP leaders, but the burst of publicity was priceless for Nehlen.

No House speaker in modern political history has lost a primary, and Ryan is hugely popular in the southeastern Wisconsin district he has represented for nearly two decades. He crushed a protest candidate in the GOP primary two years ago, winning 94 percent of the vote. The only other time he had a primary challenger was in his first race, in 1998, when he won with 81 percent of the vote.

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Our AJC colleague Ernie Suggs today quotes Atlanta Mayor Kasim Reed as saying that Democrat Hillary Clinton needs to invest up to $15 million in the coming weeks and put Georgia in her win column. Says Reed:

"I have said all along that Georgia is winnable," Reed said. "If I were in Secretary Clinton's shoes and I had an opportunity to win a state and I had a billion dollars, then $8-$15 million is a logical investment."

But let’s put on our politically jaundiced thinking caps, and view this strictly in 2016 terms – with no altruistic consideration of plowing ground for future Democratic gains in the state.

Last week's AJC poll had Clinton with a slight lead over Republican Donald Trump among likely Georgia voters, 43 to 39 percent. Libertarian Gary Johnson appears to have become a major safe space for GOP voters, pulling 12 percent.

Would it not make more fiscal sense for a secretive Super PAC – its sponsor bathing luxuriously in his or her constitutionally protected right of free speech – to drop a mere $3 million or $4 million in Georgia, pumping up the Libertarian?

Again, speaking strictly in terms of dollars, a fractured Georgia GOP appears cheaper and more achievable in the short term than a pumped-up Democratic party in Georgia.

On the other hand, this isn't an and/or choice. To one degree or another, we could see both happen.

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This clip below from last night's "All in with Chris Hayes" on MSNBC makes the more traditional argument for Democratic investment in Georgia.

In it, former NAACP leader Ben Jealous, a one-time Bernie Sanders supporter, said his party should invest in Georgia -- but not by blanketing the airwaves with ads. Instead, he trumpeted state House Minority Leader Stacey Abrams' New Georgia Project and its work trying to register minority voters.

MSNBC - Change is coming to Georgia from Georgia Democrat on Vimeo.

The clip includes this eye-opener about Trump from Jealous:  "Even David Duke is polling higher with blacks in his state right now."

For the record, the University of New Orleans' Survey Research Center reported that Duke, a former Ku Klux Klan leader running for U.S. Senate in Louisiana, had a 14 percent approval rating among black voters. Trump's favorability ratings among black voters in last week's AJC poll stood at 7 percent.

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To speak of hand-wringing in Democratic circles over the U.S. Senate race would be an understatement.

Democrat Jim Barksdale emerged as the party's challenger to Republican Johnny Isakson just days before qualifying, an unknown political novice who stepped forward after a host of higher-profile elected officials passed on the race.

Now, with polls showing the deep-pocketed newcomer within single-digits of Isakson and GOP unrest over Trump, we're hearing from some of those would-be challengers lamenting what might have been had a more established politician jumped in the contest. Instead, Barksdale has struggled to earn support within his own party, and three Georgia Democrat elders crossed party lines to endorse his GOP rival.

One well-known Democrat sighed to us that it "would have been a blast" to run with the specter of Trump weighing down the ticket. Another said it was a missed "golden opportunity." A third told us simply, a few months ago, "I should have run."

One who agreed to speak on the record is state Rep. Scott Holcomb, a Brookhaven Democrat who was among the cadre of younger Democratic office-holders who decided against challenging Isakson.

"Georgia Republicans are shifting from an offensive to a defensive strategy and they don't know what to do about Trump - should they embrace him or reject him?" he said. "The top of the ticket is going to impact every race in Georgia this year, and Republicans are going to have to pick their poison -- express their loyalty to Trump or rebuke the leader of the party."

What's harder for Isakson's would-be challengers to stomach: Barksdale got in the race in mid-March, at a time when Trump was already well on his way to becoming the GOP's nominee. In other words, they could have seen this coming.

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Speaking of the U.S. Senate race, Republican incumbent Johnny Isakson unveiled a more than 1,600-person reelection leadership team that includes virtually every elected Republican official in Georgia, as well as former Democratic governor and U.S. senator Zell Miller.

The list is a striking one, especially compared to the size of Isakson's competitor's teams. It includes representatives in all 159 counties.

On the list: U.S. Sen. David Perdue, former Republican U.S. senators Saxby Chambliss and Mack Mattingly, Gov. Nathan Deal and other top leaders: Lt. Gov. Casey Cagle, Secretary of State Brian Kemp and Attorney General Sam Olens. The list goes on from there.

Miller, a conservative Democrat who often broke with his party in the Senate, endorsed Michelle Nunn for Senate two years ago but also split his ticket, backing GOP Gov. Nathan Deal. He's the latest Democratic elder in Georgia to back Isakson's quest for a third term.

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One of the most intriguing names on the list of dozens nominated for two new Georgia Supreme Court posts is DeKalb State Court Judge Dax Lopez.

You'll recall that Lopez was President Barack Obama's nominee for a U.S. District judgeship last year. A rare three-fer - Lopez is Jewish, Republican and Hispanic - his nomination was blocked by U.S. Sen. David Perdue after anti-illegal immigration forces in Georgia pointed to his past association with Latino advocacy groups.

And the same critics who lobbied Perdue to scuttle Lopez's nomination are at it again, casting him as an "anti-enforcement" judge.

Don't count him out. Gov. Nathan Deal, who makes the final pick, has shown he's not afraid of bucking the party's right flank several times already this year.

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Five LGBT advocacy groups created a platform aimed at tracking discrimination against transgender and other students who don't conform to a gender in Georgia schools.

The five backers --Lambda Legal, Georgia Equality, the Anti-Defamation League, Georgia Safe Schools Coalition and the Cay, Lesbian and Straight Education Network Atlanta -- issued this joint statement about the Georgia Transgender Student Rights Watch:

"Our schools' first job is to provide safe and affirming environments for all our youth to learn and thrive. From the use of declared names and pronouns, to restrooms, locker rooms, sports, uniforms, and extracurricular activities, school districts should respect the gender identity of all students, including transgender students. No student should ever have to go through the experience of feeling unwelcome at school or on a college campus."

Georgia was one of 11 states to sue the Obama administration in May over a directive to public schools over bathroom rules that allow transgender  students to use bathrooms that match their gender identity. Opponents described the directive as "federal overreach," while supporters said it bolstered civil rights.