Mitch McConnell
U.S. Senate Minority Leader Mitch McConnell (R-KY) addresses supporters at his midterm election night victory rally in Louisville, Kentucky, Nov. 4, 2014. REUTERS/Shannon Stapleton

Senate Minority Leader Mitch McConnell successfully fended off Democratic challenger Alison Lundergan Grimes on Tuesday. A last-minute effort by Democrats to boost Grimes, Kentucky's secretary of state, over the veteran Republican proved unsuccessful for the state's only current female constitutional officer, as both sides spent millions to sway voters.

McConnell is expected to become majority leader if the Republicans take the Senate after Tuesday's midterm elections. The Associated Press called the race for McConnell shortly after all the polls in the state closed at 7 p.m. EST. This was McConnell's sixth consecutive victory in Kentucky Senate races. He was first elected to the upper chamber in 1984.

McConnell led the polls for the duration of the campaign, but his inability to poll above 50 percent or lead Grimes, an attorney, by more than the margin of error left a tiny shred of hope for Democrats. Early voting analysis showed she barely took a majority of women voters.

Unseating McConnell, who has been the Senate minority leader since 2007, was viewed as a golden prize in a year when many Democrats struggled. Grimes' campaign came under fire from some Democrats, who accused her of missing opportunities to capitalize on McConnell’s unpopularity. National Democrats didn’t infuse cash into the campaign until the last few weeks when they launched a series of attack ads.

The race became a series of aggressive attacks by both candidates and polls showed most voters weren’t casting their ballot with any level of excitement for either candidate. Grimes, the daughter of a former Kentucky Democratic chairman and state representative, garnered support predominately by voters who didn’t like McConnell. And McConnell’s support came from voters who didn’t like President Barack Obama.

Democratic Rep. Jim Clyburn of South Carolina said on Tuesday Grimes “botched” an opportunity by declining to answer whether she voted for Obama for president in 2008 and 2012 in an interview with the Louisville Courier-Journal editorial board last month. “I don’t think her [polling] numbers started to plummet until after she botched that question so significantly,” Clyburn said Tuesday morning on MSNBC.

The two feuded over some policy issues. McConnell sought to position himself as a close friend of the coal industry and painted Grimes as a support of job-killing regulations.

Former U.S. Secretary of State Hillary Clinton and Democratic Sen. Elizabeth Warren of Massachusetts both traveled to Kentucky to campaign for Grimes. Several Republicans also traveled to the state, including Louisiana Gov. Bobby Jindal and Kentucky Sen. Rand Paul.