Going into the final 24 hours, many analysts say the race between Claire McCaskill and Jim Talent for the Missouri Senate seat remains the closest race in the country. A poll released over the weekend showed McCaskill leading Talent 46 percent to 45 percent, well within the margin of error. A CNN poll released last Tuesday showed them tied at 49 percent.

When State Auditor Claire McCaskill ran for governor in 2004, Republican Matt Blunt chipped away at her support, especially among women, by releasing a TV campaign ad that criticized her husband's ownership of nursing homes and McCaskill's oversight of them. It was very likely a major factor in her loss then, which was by a margin of less than 3 percentage points. So it's no surprise that her race to unseat incumbent Sen. Jim Talent, which has remained in a virtual dead heat for weeks, is now focused increasingly on her wealth and her husband's tax returns.

Just five weeks from the midterm election, the highly competitive Senate race in Missouri–which most analysts say is crucial if Democrats want to win the six seats they need to take back the Senate–remains too close to call.

The first two weeks of September will be big for incumbent Sen. Jim Talent and opponent Democratic State Auditor Claire McCaskill -- at least for fundraising.

Claire McCaskill, the Democratic state auditor trying to unseat Sen. Jim Talent in the Missouri Senate race, received an untraditional endorsement this week from country music superstar Willie Nelson.