(CNN) -- Sens. Barack Obama and John McCain are starting the week reaching out to two crucial voting blocs -- Hispanic and African-American voters.
Both candidates are speaking before the National Council of La Raza, one of the country's largest Hispanic organizations.
Obama on Sunday told the group the Latino community holds the election in its hands.
"I know how powerful this community is. Just think how powerful you could be on November 4 if you translate your numbers into votes," he said as he encouraged them to register to vote.
Obama also told the crowd he would make immigration reform a priority as president.
"Not just because we need to secure our borders and get control of who comes into our country. And not just because we have to crack down on employers abusing undocumented immigrants. But because we have to finally bring those 12 million people out of the shadows," he said in San Diego, California.
"Yes, they broke the law. And we should not excuse that. We should require them to pay a fine, learn English, and go to the back of the line for citizenship -- behind those who came here legally. But we cannot -- and should not -- deport 12 million people. That would turn American into something we're not; something we don't want to be."
McCain, the presumptive Republican presidential nominee, was scheduled to address the group on Monday.
The event marks the last of three major Hispanic and Latino organizations the candidates are appearing before this summer.
Both candidates last week spoke to the League of United Latin American Citizens.
Previously, the two spoke at the annual conference of the National Association of Latino Elected and Appointed Officials. Watch what the candidates are up to this week »
As many as 10 million Latinos could cast ballots in the fall, possibly swinging some important battleground states such as Florida.
Republican strategists have said McCain has to do well with Hispanic voters to win in November. When President Bush was re-elected in 2004, he received 44 percent of the Hispanic vote, but that was before the divisive political debate erupted over illegal immigration.
McCain is seen as a moderate Republican when it comes to immigration reform, but the conservative base of his party has taken a hard-line approach on the issue.
In 2005, McCain angered some in his party when he and Democratic Sen. Ted Kennedy unsuccessfully pushed for a comprehensive immigration reform bill that included a path to citizenship. McCain now says he would focus first on securing the borders before offering other ways to deal with illegal immigration.
McCain has a new campaign commercial on the air in New Mexico, Nevada and Colorado -- three states where Spanish-speaking voters are a powerful force.
The ad salutes Hispanics who have served the country.
"When you go to Iraq or Afghanistan today, you're going to see a whole lot of people who are of Hispanic background. You're even going to meet some of the few thousand that are still green card holders who are not even citizens of this country, who love this country so much that they're willing to risk their lives in its service in order to accelerate their path to citizenship and enjoy the bountiful, blessed nation.
"So let's, from time to time, remember that these are God's children. They must come into our country legally, but they have enriched our culture and our nation as every generation of immigrants before them," McCain says in the ad.
Both candidates also turn their attention to the NAACP this week, with Obama speaking in front of their national convention in Cincinnati, Ohio, on Monday and McCain delivering his speech on Wednesday. Watch what's expected at the NAACP convention »
Obama's speech will be his first time in front of a large black organization since Jesse Jackson apologized for suggesting that Obama talks down to African- Americans.
According to polls, Obama has overwhelming support among black voters.
Obama on Sunday also addressed the American Federation of Teachers Convention. He spoke before the Chicago convention via satellite from San Diego.
Sen. Hillary Clinton, Obama's former rival, spoke before the same group on Saturday.
McCain had no public events scheduled Sunday.
Nationwide, Obama leads McCain by four points-- 47 to 43 percent, according to CNN's poll of polls.
The poll of polls is an average of three surveys: Gallup tracking (July 9-11), Newsweek (July 9-10), and CNN/Opinion Research Corp. (June 26-29).
The error margin for this poll cannot be determined.
CNN's Paul Steinhauser contributed to this report.