Wealthy candidates on both sides of the aisle are turning to their personal fortunes to boost their campaigns in the final days before Election Day.

Joe O'Dea, the Republican Senate candidate in Colorado, invested $1 million of his own cash into his campaign on Monday. Meanwhile, Trudy Busch Valentine, a Democratic Senate candidate in Missouri, added $2 million to her campaign coffers from her own fortune the same day, according to Punchbowl News.

O'Dea's investment comes after he put an additional $500,000 into his campaign on Oct. 28. Many candidates for Colorado's top offices have large personal fortunes, with all four candidates in the Senate and gubernatorial races reporting more than $1 million in annual income, according to Axios.

Republican Dr. Mehmet Oz has also bankrolled his campaign with his vast personal wealth, investing nearly $27 million into his contest against Democrat John Fetterman.

TEACHERS UNIONS SPEND BIG ON DEMOCRATS AHEAD OF MIDTERM ELECTIONS

Joe O'Dea

Joe O'Dea, Republican nominee for the U.S. Senate seat held by Democrat Michael Bennet, speaks during a primary election night watch party, late June 28, 2022, in Denver. (AP Photo/David Zalubowski, File) (AP)

TOP TRUMP ADVISERS LAUNCH MAGA INC. SUPER PAC TO SPEND FREELY IN MIDTERMS

O'Dea is the underdog in his race against Sen. Michael Bennet, D-Colo., with the incumbent leading the race 49% to 42% in polling.

O'Dea has run a moderate campaign, distancing himself from former President Donald Trump and saying he opposed the Supreme Court's decision to overturn Roe v. Wade. He has enjoyed widespread support from conservative opponents of Trump, but Trump himself has urged Republicans not to support him.

"MAGA doesn't vote for stupid people with big mouths," Trump wrote of the candidate in October, calling him a "Republican in name only."

Nevertheless, Senate Majority Leader Mitch McConnell's super PAC, the Senate Leadership Fund, threw its weight behind O'Dea's campaign, donating $1.25 million to O'Dea's super PAC, the American Policy Fund.

Mitch McConnell walking

Senate Minority Leader Mitch McConnell, a Republican from Kentucky, walks to the Senate floor at the U.S. Capitol in Washington, on Tuesday, Jan. 18, 2022. Photographer: Eric Lee/Bloomberg via Getty Images (Eric Lee/Bloomberg via Getty Images)

Personal wealth has also become a defining factor in Washington's gubernatorial race, where Nike co-founder Phil Knight has bankrolled opponents of Democratic candidate Tina Kotec.

Knight, 84, helped to kickstart a campaign from Betsy Johnson, a former Democrat running as an independent, who is serving as a major spoiler for Kotek.

Johnson's candidacy is giving Republican Christine Drazan the opportunity she needs in a liberal electorate no longer confident in the state's recent far-left policies.

CLICK HERE TO GET THE FOX NEWS APP

Oregon has not elected a Republican governor since 1982, but polls show Drazan with a solid chance of taking the election. An Oct. 13 polling average from FiveThirtyEight has Drazan at a 3-point lead over Kotek, with 37.4% and 34.3%, respectively. Meanwhile, Johnson sits at just 16.4% support.