With less than one month to go until Election Day, Democrats in several key U.S. Senate races, including Colorado Senator Michael Bennet, are accusing foreign interests of backing Republicans like Weld County District Attorney and Bennet opponent Ken Buck. He and other Republicans reportedly received the support via contributions from the U.S. Chamber of Commerce, which accepts foreign dues and donations, according to The Hill, leading liberal groups and political campaigns to chide those who've accepted them or who haven't spoken out against Chamber-sponsored attack ads.

"Why won't Ken Buck stand up against the practices of these shady special interests orchestrating attacks on his behalf and denounce the practice of accepting overseas expenditures to fund smear campaigns?" says Trevor Kincaid, a spokesman for Bennet's campaign. A spokesman for Buck, Owen Loftus, counters that Buck's campaign does not control ads aired by the Chamber.

While mainstream outlets focus on Buck's campaign money, local left-leaning websites are reviewing what ColoradoPols calls his "woman problem," adding that a rumored October surprise from the Bennet camp might not help Buck's image with some female voters. And a 2005 alleged rape victim from Weld County is speaking out against Buck for the way he handled her case, writes The Colorado Independent, which obtained a tape of a conversation the victim had with Buck, who "appears to all but blame her for the rape and tells her that her case would never fly with a Weld County jury."

Meanwhile, Bennet has added a new name to his list of supporters: Bill Clinton, who had endorsed Bennet's primary challenger, former state House Speaker Andrew Romanoff. Clinton will rally voters October 18 at the Evie Garret Campus (via The Associated Press). First Lady Michelle Obama is also expected to campaign for Bennet in Colorado this month (via The Wall Street Journal).

Vanessa Martinez contributed to this post.