Local Democrats hope former president's star power can rally base to vote for Tom Barrett over incumbant who leads in polls

Bill Clinton will travel to Wisconsin on Friday to campaign in the state's recall election amid accusations from local activists that the Obama administration has failed to get behind their bid to oust Republican governor Scott Walker.

The Democratic National Committee announced the former president's

trip on Thursday in the hope that a high Democratic turnout could overturn Walker's narrow but consistent poll lead of around seven points.

Clinton was expected to campaign in downtown Milwaukee, which has a sizeable African American population, to try to fire up the party's base in advance of next Tuesday's vote.

Tom Barrett, the Milwaukee mayor and Democratic challenger for the

governorship, has trailed in polls, but analysts said a late surge of

enthusiasm could clinch victory.

Clinton, in his heyday the nation's most formidable campaigner, will be the highest profile Democrat to campaign for Barrett. Local activists have lobbied Clinton for weeks.

"President Clinton is a true public servant who has dedicated his career to helping middle-class Americans and those trying to reach the middle class achieve the American Dream," said Debbie Wasserman Schultz, chairwoman of the Democratic National Committee, who announced the trip.

"Having just been in Wisconsin this week, I know how important the recall election is and how dedicated Democrats and Wisconsin's middle class families are to this effort."

Until now Wasserman Shultz has been the most senior Democrat to campaign in the state. Martin O'Malley, who chairs the Democratic Governors Association, was due in Wisconsin on Thursday.

Walker has had Republican big-hitters such as Chris Christie, Bob McDonnell and Bobby Jindal, respectively the governors of New Jersey, Virginia and Louisiana, as well as Senator Marco Rubio of Florida batting for him in the state. Nikki Haley, the governor of South Carolina, was due to campaign with Walker on Friday.

As a swing state in presidential elections next week's vote is widely seen as a dress rehearsal for the White House race. Walker, a tea-party favourite, defeated Barrett in 2010 but his subsequent drive against collective bargaining rights of public sector workers triggered a union-led revolt which produced next week's recall vote. A well-funded and organised Republican fight-back has shored up the governor's support and put Democrats on the defensive.

The White House has kept its distance from the battle. Obama has endorsed Barrett but not campaigned in the state. Nor has vice-president Joe Biden. On Friday, Obama is due in Minneapolis.

A poll released by the Marquette Law School found that Walker and Obama were both narrow favourites to win in Wisconsin.

"One perfectly plausible outcome this year is that both incumbents carry Wisconsin, despite the partisan abyss between them and despite how polarized Wisconsin voters are along party lines," said the Milwaukee Sentinel.

"One reason this could happen is that Walker and Obama are running in different elections – June and November – that will feature a different mix of voters."