Philpot, who was at the Republican party at the Salt Lake Hilton Hotel, gave his concession speech early Wednesday morning.
Philpot spent much of his campaign linking Matheson to House Speaker Nancy Pelosi and President Barack Obama, decrying the Utah Democrat as a rubber stamp for spending programs that sent the nation spiraling into debt.
But Matheson attacked Philpot as a largely absentee state House representative who quit his term early and made questionable votes while serving in the Legislature including one where he voted against a tax on strip clubs and escort services that would have generated revenue for victims of domestic violence.
Both campaigns used aggressive ad campaigns in the past month, with Matheson buying up television time to blast his opponent while Philpot got the aid of a wealthy Republican donor to spill cash on a radio ad that drew widespread attention because it was purchased by an individual.
That individual, who called herself B. Alice Baker, was soon discovered to be Barbara Baker, the head of Challenger School and a woman who had donated more than $45,000 to conservative candidates.
At the same time, FreedomWorks, one of the organizations connected to the tea party movement, has pumped nearly $60,000 into the campaign in the last month.
Matheson had cruised to victory in the district in the past two election cycles, but the 2010 campaign figured to be tough for incumbents as the nation roiled in a recession that saw a record number of home foreclosures and unemployment numbers hit double digits though they hovered at around 7.5 percent in Utah.
Matheson, part of the so-called Blue Dogs a group of conservative Democrats in the House, distanced himself from Pelosi and Obama when pressed by Philpot. He pointed to his decision to vote against the health care reform package and his support for extending the so-called President Bush tax cuts.
But Matheson criticized Philpot for saying health care reform should be repealed outright, saying there were some aspects of the reform that merited consideration. Matheson also said he supported the Bush tax cuts because the economic recovery was still in a fragile state.
Philpot, who drew outside support from Sarah Palin and Fox News commentator Dick Morris, said Matheson abdicated his responsibility by voting for Congress to adjourn instead of pushing to make the Bush tax cuts permanent.
He also took shots at Matheson for not getting enough legislation passed in his 10 years in Congress and, in a series of hard-hitting ads, portrayed the congressman as an empty chair.
Philpot regularly asked Matheson if he would vote for Pelosi for Democratic House leader if re-elected. Matheson usually responded by saying he'd like to see other names on the list. The Pelosi tie was key to Philpot's campaign.
Matthew D. LaPlante and Katie Drake contributed to this report.