Bartlett said he has voted for every bill to put troops or build walls on the nation's borders.
The true concern, he said, is not that immigrants are in the country illegally, but that terrorists can get in.
And the real drain from illegal immigration, he said, is the burden of poor, uneducated people -- a problem among U.S. citizens, too.
On the possibility of privatizing Social Security, Bartlett said people should be free to invest their own money.
"This year, for the first time, Social Security paid out more than it took in," Bartlett said, adding that the tipping point occurred sooner than expected.
Another question was whether citizenship, as guaranteed in the 14th Amendment to the U.S. Constitution, should be granted to babies of illegal immigrants.
"I think this would be a reasonable debate to have ...," Bartlett said. "Is this really what the founders intended?"
Bartlett also talked about other government topics, such as the difference between a democracy and a republic. A democracy, he said, is majority rule, which can be the will of a lynch mob or two lions and a lamb voting on what dinner will be, while a republic follows the rule of law.
On the culture of Washington, Bartlett said: "I try to never sleep inside the Beltway. You might get Potomac Fever."
Patrick Allen, the campaign manager for Democratic Congress candidate Andrew Duck, attended the meeting and later collaborated with Duck on a press release attacking a few of Bartlett's comments.
One was a story Bartlett told about an English woman living in the U.S. who didn't want to go back to her native country to start the immigration process.
"His willingness to look the other way with one illegal immigrant, while calling for increased action against illegal immigration is just one example of the kind of Washington hypocrisy Congressman Bartlett has come to represent."
Duck, an Iraq War veteran, also seized on Bartlett's "lynch mob" comment, saying, "I put my life on the line to defend this democracy called the United States. For Congressman Bartlett to criticize democracy does not reflect well on his patriotism."
This year, Duck and J. Casey Clark are running in a Democratic primary.
Bartlett's Republican challengers are Dennis B. Janda, Joseph T. Krysztoforski, Steve Taylor and Seth Edward Wilson.
Libertarian Dan Massey and Constitution Party candidate Michael Reed also are running.