;2000 Porter lost the race for U.S. Congress in Nevada's 1st congressional district against Democratic incumbent Shelley Berkley. Berkley won 52% to 44%. ;2002 However, this immediately made him the frontrunner for the Republican nomination in the newly created 3rd District. The district had been created due to a population explosion in the Las Vegas area. Porter easily won the Republican nomination and faced Clark County CommissionerDario Herrera. The race was considered one of the hottest in the nation, in part because the district had been created as a "fair fight" district. However, Herrera's campaign foundered due to ethical problems, most notably when he was paid $50,000 by the Las Vegas Housing Authority for "public relations work." Porter won 56% to 37%. ;2004 Porter defeated Tom Gallagher by a wider-than-expected 14-point margin. ;2006 Porter won re-election over his opponent Tessa Hafen, former press secretary for U.S. Senator Harry Reid, with 48% to 47%. ;2008 The closeness of the 2006 race, combined with the marginal nature of the district, led Democrats to target Porter for defeat in 2008. After their initial choice, Clark County Prosecutor Robert Daskas, dropped out for family reasons, the Democrats quickly recruited State Senate Minority Leader Dina Titus, the unsuccessful Democratic candidate for governor in 2006. In the November 2008 election, Porter lost only the second general election of his career, taking 42 percent of the vote to Titus' 47 percent. Porter was likely hampered by a sharp increase in Democratic registration, as well as Barack Obama carrying the district with 55 percent of the vote. Additionally, Porter was seen as a potentially strong challenger to Harry Reid, the Democratic Majority Leader of the U.S. Senate who was up for reelection in 2010, so it was thought that Reid targeted Porter for defeat in order to eliminate him as a possible opponent..
Jon Porter voted against tax incentives for renewable energy, tax incentives for bio fuels, and removing oil & gas exploration subsidies. He had a 0% rating on energy independence from the Campaign for America's Future, a progressive political organization, and voted twice to implement George W. Bush's national energy policy.
On July 19, 2007, Porter voted for an amendment that would have cut off funding for Planned Parenthood and other groups which provide abortion services. In September 2004, Porter voted to amend the United States Constitution to ban same-sex marriage.
Labor
In January 2007, Jon Porter voted against raising the federal minimum wage to $7.25. In March 2007, Porter voted against restricting employer influences in union organizing. The AFL-CIO considers Porter to have an anti-union voting record.
Civil rights
The NAACP agreed with 39% of his votes on their key issues, and describe his record as 'mixed'. In December 2005, Jon Porter voted to make the PATRIOT Act permanent.
Illegal immigration
Porter opposed requiring hospitals to notify immigration authorities of illegal immigrants seeking treatment.