After his good friend Texas Gov. Rick Perry dropped out of the presidential race Thursday, Virginia Gov. Bob McDonnell officially endorsed former Massachusetts Gov. Mitt Romney Friday morning, on the eve of the South Carolina primary.

"I'm delighted to be endorsing him," McDonnell said. "It's the right time, the first primary in a Southern state."

"There were a lot of factors, but it's the right time to get out front and support who I think is the right person to beat President Obama," McDonnell said in a phone interview with reporters. McDonnell was in New York for economic development meetings and planned to fly to South Carolina to campaign for Romney at 4 p.m. on Friday and Saturday morning, the day of the primary.

Romney is the best candidate, McDonnell said, primarily because of his experience as a governor.

"I’ve been thinking about this for awhile," McDonnell said. "He's the best candidate for our team, a current or former governor. When I look at what’s wrong in Washington—a lack of leadership, budgets that can’t get balanced, 35 months of unemployment over 8 percent—we need an executive, and that's Mitt Romney."

As a Southern governor, pundits say McDonnell's endorsement could boost Romney's chances to come out on top in the South Carolina primary, where Romney is battling former Speaker Newt Gingrich, a McLean resident, for the top spot. Perry threw his support behind Gingrich.

Regarding Gingrich's possible problems related to charges by former wife Marianne Gingrich, McDonnell said that in the end, a politician's personal life is on the back burner compared to the problems voters face today. "I think Speaker Gingrich handled that question well last night [in the televised debate]," McDonnell said. "I can tell you, what’s important to voters now is: 'How do we create jobs? How do we secure borders?' That's what matters, that's what people are going to vote on."

McDonnell announced his endorsement of Romney Friday morning via his Twitter feed at 8 a.m.: "I am pleased to announce my endorsement of Governor@MittRomney for President."

McDonnell, who chairs the Republican Governors' Association, is also touted as a possible vice presidential choice. "Any speculation is way too premature," he said on Friday.