2. What will happen to all this personal information once the campaign is over?
It's hard to know.
The campaign's privacy policy reserves the right to share the personal information it collects "with candidates, organizations, groups or causes that we believe have similar political viewpoints, principles or objectives."
The campaign wouldn't comment about any future plans but said its track record demonstrated its approach to privacy protection.
After the 2008 election, Obama's list of 13 million email addresses was not given to other candidates or used by the White House. Obama launched "Organizing for America," a Democratic National Committee outreach program that drew on Obama's wide network of supporters to generate support for the president's agenda.
"This campaign has always and will continue to be an organization that respects and takes care to protect information that people share with us," spokeswoman Katie Hogan said.
But the privacy policy shows the campaign is reserving the right to share their increasingly rich database. And some experts are wondering what Obama will do with it once the campaign is over.
"As a voter, I would feel a lot more comfortable if campaigns gave voters the option of whether or not they could pass their information on to other groups," said Andrew Raisej, founder of Personal Democracy Forum and TechPresident, a site focused on the ways technology affects politics.
From a voter's perspective, "the fact that I gave the Obama campaign $10 for six months, or emailed the campaign 10 times, may not be information that I want anyone else to know," Raisej said.
Lillie Coney, associate director of the Electronic Privacy Information Center, said she's "never heard anyone complain" about Obama's 2008 campaign giving their personal information away.
"The success of the Obama campaign in 2008 in getting millions of people to log onto their website to give personal information and volunteer and do all sorts of things for the campaign hinged on trust," she said. "People did not believe that that information was going to go anywhere."
Any choice to share supporters' information should take their preferences into account, Coney said. A campaign could easily create a checklist of politicians and organizations, allowing users to grant permission to share with some groups and not with others.
3. Is there any way to erase yourself from the campaign's database?
As far as we can tell, no.
President Obama's "Consumer Privacy Bill of Rights," released last month, says that consumers' right to control their own personal data "includes a right to withdraw consent to use personal data that the company controls."
The Obama campaign does make it easy to unsubscribe from email, text messages, or newsletters from the campaign. But we couldn't find any way to unsubscribe yourself from their database -- and the campaign wouldn't comment. There's also no apparent way to see what information the campaign is storing about you.