Obama just helped Clinton AND Trump

If you want to alienate people, start talking about controversial topics like abortion rights, immigration, affirmative action and labor unions — all topics the next U.S. Supreme Court will decide on.

Those fiery issues don't make for great dinner conversations, but for politicians, they are the bread and butter for votes. Nothing gets people to the polls faster than a hot button issue that angers them.

Democratic presidential candidate Hillary Clinton and Republican presidential candidate Donald Trump
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Democratic presidential candidate Hillary Clinton and Republican presidential candidate Donald Trump

That's why President Obama may have just fired up the base for both Hillary Clinton and Donald Trump with his Supreme Court nominee announcement of federal appeals court judge Merrick Garland. He also may have divided the country even further in the process, especially if the Senate refuses to hold hearings or vote on Garland's nomination.

Clinton can now continually remind voters on the campaign trail that the Republican-controlled Senate refused to vote on a Supreme Court justice nominated by the president. She can also play the race card on immigration and affirmative action, and pit middle classes against each other with the labor union debate, saying the Senate doesn't want a justice that represents their concerns.

Sure, minorities and union workers will have more incentive to go to the polls with more on the line, but as we edge closer toward November, this will also lead to a more disenfranchised and divided electorate that is angrier than ever. Those on both sides of these controversial issues will become more vocal, especially as politicians use it as anger bait.

Around 30 senators are up for re-election this year (mostly Republicans) and you can bet those heated topics will all become talking points on the campaign trail. When listening to their stump speeches, voters at those campaign stops will start to feel like your angry Uncle Larry who tries to stir up trouble at the dinner table. It doesn't lead to any productive solutions but his discussion gets everyone riled up.

Polls show Trump supporters are the most disenfranchised and angry group of voters. In surveys, his supporters say they feel Washington doesn't have their interest and plays by their own rules. This GOP tactic to not even hold hearings or allow for a vote for Garland plays right into their sentiment that Washington politicians only care about themselves.

Sure, most Trump voters don't agree with Obama's policies — or anything he says — but tea party supporters do care about the Constitution. They may not like what Obama does, but deep inside, they know they can't selectively support when to agree and not agree with the Constitution.

The GOP's decision to ignore Obama's Supreme Court nominee may also give Trump a card to play later if he falls short in the delegate count. It's unlikely Trump will publicly invoke any support for Obama's Supreme Court nomination, but if party leaders decide to push another nominee ahead of Trump at their convention, he has a stronger argument to reinforce with the public why the GOP makes their own rules, regardless of what the public thinks.

I don't think the GOP's resistance to holding a hearing on Garland will mean voters will take it out on them in the polls come November, but I think it will lead to a lot of fiery conversation leading up to it!

Commentary by Mark Macias, head of Macias PR, a global public-relations firm, that has run media and branding campaigns for politicians, tech start-ups, financial firms, nonprofits and companies. He's also author of the book, "Beat the Press: Your Guide to Managing the Media." Follow him on Twitter @markmacias.

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