Sen. Jon Tester, D-Mont., said Friday he won't keep campaign donations he received last year that have now been tied to a disgraced Democratic fundraiser if the donations are found to be improper.

"If a donation to Sen. Tester is shown to have been made illegally, he would obviously return it or donate it to charity," said Matt McKenna, a Tester spokesman.

Tester received $3,750 last year from people linked to Norman Hsu, a New York clothing executive who helped raise more than $1 million for Democratic candidates in the last four years. Tester received no money from Hsu himself.

Chris Wilcox, executive director of the Montana Republican Party, said Friday Tester should return the money and not wait to see if the donations are illegal.

"Obviously, they need to give the money back," Wilcox said. "It's money that has a taint on it at this point. Jon Tester ran as a guy who was going to be completely aboveboard."

The Wall Street Journal reported last week that six members of a middle-income California family had given $45,000 to Sen. Hillary Clinton since 2005. The family, William and Alice Paw and their adult children, made donations that closely tracked those of Hsu, who once listed their modest address as his own.

Hsu has since been arrested on an unrelated, 15-year-old theft conviction, and the Washington Post has reported that Justice Department officials are looking into Hsu's fundraising to see if an investigation is necessary.

Hsu had been a successful fundraiser for Democratic candidates, and some are now wondering if he funneled money through acquaintances or friends to get around caps on the amount a single person can give to political candidates or groups.

However, the Wall Street Journal also reported that there is no record of Hsu ever reimbursing the Paw family.

Records show Tester received six donations last summer and fall from people identified in the Wall Street Journal as Hsu associates. Tester received a total of $3,750 in Hsu-related donations, records show, including $2,000 from two members of the Paw family on Sept. 18, 2006.

As the scandal unfolds, Democrats have been scrambling to distance themselves from Hsu and his cash. Presidential candidate and New York Senator Hillary Clinton announced this week she will give to charity $23,000 her campaign received directly from Hsu.

Illinois senator and presidential hopeful Barack Obama also received money directly from Hsu, which has likewise either been returned or donated to charity.

Tester, however, is not alone among candidates who received money merely "linked" to Hsu and who are now either keeping the money or waiting to see if the donations are illegal.

Hillary Clinton's campaign has chosen to keep money Hsu merely helped raise. Missouri Dem. Sen. Claire McCaskill received more than $18,000 in donations associated with Hsu, including some from the Paw family. She has chosen to keep the money unless it has been determined to be illegal.

Records show Hsu made his first political donation in September of 2003 to presidential hopeful Sen. John Kerry, D-Mass.

Since then, Hsu and his associates have made hundreds of donations to dozens of Democratic candidates across the nation.

Sen. Max Baucus, D-Mont., received no money from Hsu, the Paw family or Hsu's associates.

Scandalous campaign contributions played a role in Tester's 2006 election. Tester unseated Republican Sen. Conrad Burns amid a scandal involving Burns' receipt of more than $150,000 in donations from disgraced lobbyist Jack Abramoff, his clients and associates. Months after the criticism, Burns either returned or donated the money.