One day after paying tribute to Lyndon B. Johnson, whose landmark Civil Rights Act helped swing open doors of opportunity for President Obama and other present-day African-American lawmakers, the president addressed Republican efforts to weaken another major cause championed by his Democratic predecessor: voting rights.

Speaking at the National Action Network Conference in New York, Obama noted how voting is the greatest equalizer.

"Voting is a time when we all have an equal say: Black or white; rich or poor; man or woman. It doesn't matter. In the eyes of the law and in the eyes of our democracy, we're all supposed to have that equal right to cast our ballot to help determine the direction of our society," he said. "The principle of one person-one vote is the single greatest tool we have redress an unjust status quo."

Republicans argue that new voting laws simply aim to reduce fraud at the ballot box. But Democrats counter that there is little and in many cases no evidence of fraud and that the GOP's true desire is to disenfranchise minorities, low-income voters, the elderly and young adults who tend to vote for Democrats. Facing a difficult midterm election season that could determine the fate of the rest of his time in the White House, Obama and his party are laser-focused on voting rights and motivating people to turn out at the polls in November.

"The right to vote is threatened today in a way that it has not been since the Voting Rights Act became law nearly five decades ago. Across the country Republicans have led efforts to pass laws making it harder, not easier for people to vote," the president said.

Women who registered to vote before marriage may be turned away because their driver's license has their married name, Obama added. Senior citizens who've voted for decades may not be allowed to vote because they don't have a particular ID. Others may not be able to get a government-issued ID if they don't have a passport or a copy of their birth certificate.

"And just to be clear, I know where my birth certificate is, but a lot of people don't. I mean it's still up on a website somewhere," the president said in a joke directed at birther conspiracy theories that he is not an American citizen. "You remember that? That was crazy."

Obama said that he supports "reasonable attempts to secure the ballot," but opposes "requiring an ID that millions of Americans don't have." In addition, he said the minuscule amount of voting fraud that takes place doesn't justify efforts to disenfranchise people.

"Let's be clear: The real voter fraud is people who try to deny our rights by making bogus claims about voter fraud," the president said.

In addition to addressing stricter laws, voting rights activists are fighting to dull the potentially adverse effect of the Supreme Court ruling last year overturning a key provision in the Voting Rights Act that required all or parts of states with a history of discrimination in voting to get federal approval before changing election laws.

Attorney General Eric Holder in remarks delivered at the NAN conference Wednesday vowed that protecting voting rights would be a priority for the Obama administration.

Vice President Joe Biden also weighed in on the issue this week.

"I've got to tell you, if someone had said to me 10 years ago I had to make a pitch for protecting voting rights today, I would have said you've got to be kidding,” Biden said in a Democratic National Committee video promoting its Voter Expansion Project. "It's time to stand up and to fight back."

Follow Joyce Jones on Twitter: @BETpolitichick.

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