[2][3] Cao was the only Republican congressman to vote for the draft Obamacare, known as Patient Protection and Affordable Care Act, in November 2009.

In 1975 Anh Cao was eight years old when he, his siblings and his uncle arrived as refugees in the United States, where they were resettled in Houston, Texas.

He volunteered at Boat People SOS (BPSOS) to assist Vietnamese refugees and immigrants and help organize Vietnamese-American communities in the state toward self-sufficiency.

[10] Cao was the least affluent member of Louisiana's delegation in Congress: as of 2009 his assets were no greater than $195,000 and his potential liabilities amounted to $215,000, including student loans for himself and his wife.

After the swearing-in by Speaker of the House Nancy Pelosi, Jefferson Parish Judge Robert Murphy re-administered the oath in Cao's new office.

[12] Despite the tardiness of the election date, Cao rapidly set up his office and staff and gained committee assignments for the 111th Congress.

[13] In the speech, which was broadcast on C-SPAN, Cao said, of Vietnam War veterans, "I am pleased that I, a direct beneficiary of their service, can take part ... in this historic event."

[14][15] With the support of congressional Republicans who collectively had an entitlement to 40 percent of earmarks for federal projects, Cao worked to "bring home the bacon" for his district.

[18] In June 2010, Cao was one of only two Republicans to vote in favor of the DISCLOSE Act, intended to limit spending on political campaigns by corporations in the wake of the Supreme Court's decision in Citizens United v. Federal Election Commission.

Writing in the Times-Picayune, Jonathan Tilove observed the notability of 2113 in the Rayburn Building due to its being, as Jefferson's former location, the only congressional office ever raided by the FBI.

George Mason University political scientist Michael K. Fauntroy described Cao's expressed interest in joining as "a very smart move".

James Gill defended Head's support for Cao (who is not white but Asian) and asserted it was based not on race but that "Jefferson ... is morally unfit for any public office.

[38] On February 25, 2009, Cao grabbed headlines by announcing that his staff members were investigating the Federal Emergency Management Agency (FEMA) office in New Orleans.

Cao, whose aversive relationship with the agency had started during his time as a community activist for victims of Hurricane Katrina, accused FEMA of a host of malfeasance charges, including "widespread complaints of discrimination, sexual harassment, ethics violations, nepotism and cronyism.

"[40] The next day Cao's call for the resignation of Doug Whitmer, head of FEMA's New Orleans office, was bolstered by United States Senator Mary Landrieu,[41] whereupon the story spread on CBS News.

"[46] On March 5, 2009, Cao joined Napolitano, Jindal, Housing and Urban Development Secretary Shaun Donovan, Louisiana Lieutenant Governor Mitch Landrieu, U.S. Representative Charlie Melancon, and other federal, state, and local officials on a tour of damaged areas in New Orleans, including the campus of Southern University at New Orleans (SUNO), where the group was led by SUNO President Victor Ukpolo.

[48] The segueing event on Cao's agenda during the same day was a fund-raising cocktail party at the home of bankers Stephen and Dana Hansel at which the admission contribution was $1000 a person and an unexpected guest was former Speaker of the House Newt Gingrich[49] who was en route to lead a discussion in James Carville's political science class at Tulane University.

[50] The Times-Picayune, in an editorial on March 19, 2009, praised Ukpolo and Cao in their efforts to secure funding for restoration of SUNO's campus.

[53][54] Yet Cao, because of concerns of alleged public funding for elective abortion provisions, joined the rest of his party in opposing the final version, the Patient Protection and Affordable Care Act.

[64] On November 30, the New Orleans Times-Picayune endorsed Cao in an editorial,[65] while on its op-ed page columnist James Gill stated that Jefferson's reelection "is not going to happen".

[67] Cao's candidacy received the endorsements of the Alliance for Good Government, the Family Research Council's Action PAC, Jefferson Parish Sheriff Newell Normand, Louisiana Governor Bobby Jindal, Jacquelyn Brechtel Clarkson, Stacy Head, and singer/entertainer Pat Boone.

The New Orleans Gambit Weekly, citing its opposition to Jefferson's alleged corruption and to Cao's noncommittal statements on embryonic stem-cell research, made no endorsement.

References were made to Democratic Speaker of the House Nancy Pelosi's removal of Jefferson from the House Ways and Means Committee and entailed what USA Today termed a "barrage"[71] of automated telephone calls, including from a woman who identified herself as "Katy" and who cited Jefferson's federal indictment on 16 counts of corruption.

[77] A post-election map analysis by the Times-Picayune showed the election result as having depended on higher turnout in the precincts favorable to Cao.

[78] After speaking by telephone four days after the election, on December 31, 2008, Wednesday, Jefferson and Cao met cordially at the home of New Orleans' Liberty Bank CEO Alden McDonald to discuss the transition.

Wrote Jeff Crouere in his column Ringside Politics, "The victory strikes a major blow against the reputation of Louisiana as a corrupt state".

Flanagan ousted scandal-plagued House Ways and Means Committee chairman Dan Rostenkowski in 1994, only to be roundly defeated for reelection after one term in his heavily Democratic Chicago-based district by future Illinois Governor Rod Blagojevich.

[84] As expected, Cao lost his reelection bid in a landslide to Democratic State Representative Cedric Richmond, an African American.

In December 2015, Cao announced that he would run for the open U.S. Senate seat being vacated by retiring fellow Republican David Vitter in 2016.

Kate and Joseph met in 1998 at the Mary Queen of Vietnam Catholic Church in New Orleans East and the family has attended there since.