Tim Kaine campaigns with Barack Obama in Virginia

Politically vulnerable Democrats across the country may be shying away from President Barack Obama. But not Virginia Senate candidate Tim Kaine.

Former Gov. Kaine on Friday got to play sidekick and opening act for Obama as the commander in chief made a three-stop campaign swing in his home state.

Kaine touted the president's economic record, praised his re-election campaign and generally fired up the crowd in his introductory speech for the president at Obama's first rally Friday, in Virginia Beach.

Kaine is waging one of the most-watched Senate campaigns in the country against former Republican Sen. George Allen in the race to succeed retiring Democratic Sen. Jim Webb. Political strategists say the race, occurring in a crucial swing state, is the down-ballot contest that will be most closely tied to the presidential race.

In many competitive states across the country, politically vulnerable Democrats are skipping attendance at this summer's Democratic National Convention, where Obama will receive the party's nomination. Others, such as North Carolina Reps. Larry Kissell and Mike McIntyre, have refused to endorse the president, and others are using advertising to directly distance themselves from Obama. But Kaine's decision to tour with Obama Friday makes clear his willingness to align himself with the president despite his low poll numbers in many competitive states.

A poll released Wednesday from Public Policy Polling (pdf) suggests that there's method behind Kaine's decision-making. "He may receive coattails from Barack Obama, who's faring quite well in the state at this point," PPP president Dean Debnam said in his analysis.

That poll showed the Senate race to currently be a tossup, with Kaine receiving 46 percent to 44 percent for Allen. The poll's margin of error was plus or minus 3.9 percentage points.

The president on Friday had Kaine as well as Democratic Sen. Mark Warner fly with him on Air Force One to their first stop in Virginia Beach, where both introduced the president.

Kaine received a shout-out when it was the president's turn to speak. "Your outstanding former governor and soon-to-be United States Senator Tim Kaine!" the president told the crowd.

Republicans used the campaign appearances as an opportunity to attack Kaine, with National Republican Senatorial Committee spokesman Brian Walsh saying in a release to reporters that "it reminds Virginians that Kaine has a record of putting his loyalty to President Obama ahead of Virginia jobs."

Walsh criticized Obama on defense cuts saying, "Virginians are rightfully left to wonder if Kaine still believes that 'everything has to be on the table' when it comes to cutting Virginia's military resources."

Friday's campaign swing feeds into Republican arguments that Kaine is too closely tied to Washington. "Tim Kaine left Virginia for Washington and was a cheerleader for massive spending," states the announcer in an attack ad released this week for Crossroads GPS.

Expect to see photos of Friday's events coming soon to an attack ad near you.